The surface of a spharical balloon is increase of its volume when its radius is 6 cm.

The surface of a spharical balloon is increase of its volume when its radius is 6 cm.
by

1 Answer

Answer :

The surface of a spharical balloon is increase of its volume when its radius is 6 cm.
by

Related questions

The volume of a spherical balloon is increasing at a rate of ` 25 cm^(3)//sec`. Find the rate of increase of its curved surface when the radius of bal

Description : The volume of a spherical balloon is increasing at a rate of ` 25 cm^(3)//sec`. Find the rate of increase of its curved surface when the radius of bal

Last Answer : The volume of a spherical balloon is increasing at a rate of ` 25 cm^(3)//sec`. Find the ... its curved surface when the radius of balloon is 5 cm.

The radius of a spherical balloon increases from 6 cm to 12 cm as air is being pumped into it. -Maths 9th

Description : The radius of a spherical balloon increases from 6 cm to 12 cm as air is being pumped into it. -Maths 9th

Last Answer : Surface area of a spherical balloon whose radius is 6 cm. = 4π × 6 × 6 cm2 Surface area of a spherical balloon whose radius is 12 cm. = 4π × 12 × 12 cm2 ∴ Ration of surface areas = 4π × 6 × 6 / 4π × 12 × 12 = 1 / 4 = 1 : 4

The radius of a spherical balloon increases from 6 cm to 12 cm as air is being pumped into it. -Maths 9th

Description : The radius of a spherical balloon increases from 6 cm to 12 cm as air is being pumped into it. -Maths 9th

Last Answer : Surface area of a spherical balloon whose radius is 6 cm. = 4π × 6 × 6 cm2 Surface area of a spherical balloon whose radius is 12 cm. = 4π × 12 × 12 cm2 ∴ Ration of surface areas = 4π × 6 × 6 / 4π × 12 × 12 = 1 / 4 = 1 : 4

The radius of a hemispherical balloon increases from 6 cm to 12 cm as air is being pumped into it. -Maths 9th

Description : The radius of a hemispherical balloon increases from 6 cm to 12 cm as air is being pumped into it. -Maths 9th

Last Answer : NEED ANSWER

The radius of a hemispherical balloon increases from 6 cm to 12 cm as air is being pumped into it. -Maths 9th

Description : The radius of a hemispherical balloon increases from 6 cm to 12 cm as air is being pumped into it. -Maths 9th

Last Answer : Find the ratios of the surface areas of the balloon in the two cases.

The radius of a spherical balloon increases from 7cm to 14cm as air is being pumped into it. Find the ratio of surface areas of the balloon in the two cases. -Maths 9th

Description : The radius of a spherical balloon increases from 7cm to 14cm as air is being pumped into it. Find the ratio of surface areas of the balloon in the two cases. -Maths 9th

Last Answer : Let r1 and r2 be the radii of spherical balloon and spherical balloon when air is pumped into it respectively. So r1 = 7cm r2 = 14 cm Now, Required ratio = (initial surface area)/(Surface area after pumping air into ... = (7/14)2 = (1/2)2 = ¼ Therefore, the ratio between the surface areas is 1:4.

The radius of a sphere decreases from 10 cm to `9.9` cm. Find (i) approximate decrease in its volume. (ii) approximate decrease in its surface.

Description : The radius of a sphere decreases from 10 cm to `9.9` cm. Find (i) approximate decrease in its volume. (ii) approximate decrease in its surface.

Last Answer : The radius of a sphere decreases from 10 cm to `9.9` cm. Find (i) approximate decrease in its volume. (ii) approximate decrease in its surface.

The rate of increase of the radius of an air bubble is 0.5 cm/sec. Find the rate o fincrease of its volume when the radius of air bubble is 2 cm.

Description : The rate of increase of the radius of an air bubble is 0.5 cm/sec. Find the rate o fincrease of its volume when the radius of air bubble is 2 cm.

Last Answer : The rate of increase of the radius of an air bubble is 0.5 cm/sec. Find the rate o fincrease of its volume when the radius of air bubble is 2 cm.

A spherical ball is divided into two equal halves. If the curved surface area of each half is 56.57 cm?, find the volume of the spherical ball.11531/cylinder-radius-halved-and-height-doubled-then-find-volume-with-respect-original-volume -Maths 9th

Description : A spherical ball is divided into two equal halves. If the curved surface area of each half is 56.57 cm?, find the volume of the spherical ball.11531/cylinder-radius-halved-and-height-doubled-then-find-volume-with-respect-original-volume -Maths 9th

Last Answer : since curved surface of half of the spherical ball = 56.57 cm2 ∴ 2πr2 = 56.57 ⇒ r2 = 56.57 / 2 × 3.14 = 9 ⇒ r = 3 cm Now, volume of spherical ball = 4 / 3 πr3 = 4 / 3 × 3.14 × 3 × 3 × 3 = 113.04 cm3

A spherical ball is divided into two equal halves. If the curved surface area of each half is 56.57 cm?, find the volume of the spherical ball.11531/cylinder-radius-halved-and-height-doubled-then-find-volume-with-respect-original-volume -Maths 9th

Description : A spherical ball is divided into two equal halves. If the curved surface area of each half is 56.57 cm?, find the volume of the spherical ball.11531/cylinder-radius-halved-and-height-doubled-then-find-volume-with-respect-original-volume -Maths 9th

Last Answer : since curved surface of half of the spherical ball = 56.57 cm2 ∴ 2πr2 = 56.57 ⇒ r2 = 56.57 / 2 × 3.14 = 9 ⇒ r = 3 cm Now, volume of spherical ball = 4 / 3 πr3 = 4 / 3 × 3.14 × 3 × 3 × 3 = 113.04 cm3

The volume of cube is increasing at a rate of `9 cm^(3)//sec`. Find the rate of increase of its surface area when the side of the cube is 10 cm.

Description : The volume of cube is increasing at a rate of `9 cm^(3)//sec`. Find the rate of increase of its surface area when the side of the cube is 10 cm.

Last Answer : The volume of cube is increasing at a rate of `9 cm^(3)//sec`. Find the rate of increase of its surface area when the side of the cube is 10 cm.

The radius of a spherical balloon increases -Maths 9th

Description : The radius of a spherical balloon increases -Maths 9th

Last Answer : Radius of the spherical balloon = r1 = 7 cm Surface area s1 of the balloon = 4 πr12 = 4 x 22/7 x 72 = 616 cm2 Radius of the spherical balloon when air is pumped into it = r2 = 14 cm Surface area S2 of the balloon = 4 πr22 = 4 x ... S 1/S 2 = 4 x 22/7 x 7 2/4 x 22/7 x14 2 = 1/4 ∴ S1 : S2 = 1 : 4

A balloon which always remains spherical, is being inflated by pumping in 900 cubic centimetres of gas per second. Find the rate at which the radius o

Description : A balloon which always remains spherical, is being inflated by pumping in 900 cubic centimetres of gas per second. Find the rate at which the radius o

Last Answer : A balloon which always remains spherical, is being inflated by pumping in 900 cubic centimetres of gas ... is increasing when the radius is 15 cm.

What is the force required (in Newtons) to hold a spherical balloon stationary in water at a depth of H from the air-water interface? The balloon is of radius 0.1 m and is filled with air. (A) 4πg/3 (B) 0.01 πgH/4(C) 0.01 πgH/8 (D) 0.04 πgH/3

Description : What is the force required (in Newtons) to hold a spherical balloon stationary in water at a depth of H from the air-water interface? The balloon is of radius 0.1 m and is filled with air. (A) 4πg/3 (B) 0.01 πgH/4 (C) 0.01 πgH/8 (D) 0.04 πgH/3

Last Answer : (A) 4πg/3

The volume of the metal of a cylindrical pipe is 748 cm^3. The length of the pipe is 14 cm and its external radius is 9 cm -Maths 9th

Description : The volume of the metal of a cylindrical pipe is 748 cm^3. The length of the pipe is 14 cm and its external radius is 9 cm -Maths 9th

Last Answer : answer:

The radius of a sphere is 8 cm and 0.02 cm is the error in its measurement. Find the approximate error in its volume.

Description : The radius of a sphere is 8 cm and 0.02 cm is the error in its measurement. Find the approximate error in its volume.

Last Answer : The radius of a sphere is 8 cm and 0.02 cm is the error in its measurement. Find the approximate error in its volume.

The volume of a sphere (V) varies directly as the cube of its radius. The volume of the sphere of radius 3 cm is ` 36 pi cm^(3)`. What is the volume o

Description : The volume of a sphere (V) varies directly as the cube of its radius. The volume of the sphere of radius 3 cm is ` 36 pi cm^(3)`. What is the volume o

Last Answer : The volume of a sphere (V) varies directly as the cube of its radius. The volume of the sphere of ... What is the volume of a sphere of radius 15 cm?

The volume of a sphere (V) varies directly as the cube of its radius. The volume of the sphere of radius 3 cm is ` 36 pi cm^(3)`. What is the volume o

Description : The volume of a sphere (V) varies directly as the cube of its radius. The volume of the sphere of radius 3 cm is ` 36 pi cm^(3)`. What is the volume o

Last Answer : The volume of a sphere (V) varies directly as the cube of its radius. The volume of the sphere of ... What is the volume of a sphere of radius 15 cm?

The radius and height of a right circular cone are 28cm & 72 cm respectively. Find its volume.

Description : The radius and height of a right circular cone are 28cm & 72 cm respectively. Find its volume.

Last Answer : Answer: A 

The radius and height of a right circular cylinder are 42 cm & 63 cm respectively. Find its volume. a) 237564 cm3 b) 349272 cm3 c) 379252 cm3 d) 453213cm3

Description : The radius and height of a right circular cylinder are 42 cm & 63 cm respectively. Find its volume. a) 237564 cm3 b) 349272 cm3 c) 379252 cm3 d) 453213 cm3

Last Answer :  Answer: B 

A hemispherical bowl is made of steel 0.5 cm thick. The inside radius of the bowl is 4 cm. What is the volume of steel used in making the bowl ? -Maths 9th

Description : A hemispherical bowl is made of steel 0.5 cm thick. The inside radius of the bowl is 4 cm. What is the volume of steel used in making the bowl ? -Maths 9th

Last Answer : answer:

A balloon, which always remains spherical, has a variable diameter `3/2(2x+1)`.Find the rate of change of its volume with respect to x.

Description : A balloon, which always remains spherical, has a variable diameter `3/2(2x+1)`.Find the rate of change of its volume with respect to x.

Last Answer : A balloon, which always remains spherical, has a variable diameter `3/2(2x+1)`.Find the rate of change of its volume ... (2)` D. `8/3 pi (2x+1)^(2)`

A balloon is inflated with helium gas at room temperature of 25 °C and at 1 bar pressure when its initial volume is 2.27L and allowed to rise in air.

Description : A balloon is inflated with helium gas at room temperature of 25 °C and at 1 bar pressure when its initial volume is 2.27L and allowed to rise in air.

Last Answer : A balloon is inflated with helium gas at room temperature of 25 °C and at 1 bar pressure when ... at which volume of the balloon can stay inflated ?

Curved surface area of a cone is 308 cm2 and its slant height is 14 cm. Find (i) radius of the base -Maths 9th

Description : Curved surface area of a cone is 308 cm2 and its slant height is 14 cm. Find (i) radius of the base -Maths 9th

Last Answer : Slant height of cone, l = 14 cm Let the radius of the cone be r. (i) We know, CSA of cone = πrl Given: Curved surface area of a cone is 308 cm2 (308 ) = (22/7) r 14 308 = 44 r r = 308 ... Total surface area of cone = 308+(22/7) 72 = 308+154 Therefore, the total surface area of the cone is 462 cm2.

The radius of a right circular cone is 3 cm and its height is 4 cm. The curved surface of the cone will be (1) 12 sq. cm (2) 15 sq. cm (3) 18 sq. cm (4) 21 sq. cm

Description : The radius of a right circular cone is 3 cm and its height is 4 cm. The curved surface of the cone will be (1) 12 sq. cm (2) 15 sq. cm (3) 18 sq. cm (4) 21 sq. cm

Last Answer : (2) 15 sq. cm

A hot air balloon has a volume of 2800 m^3 at 99°C. What is the volume if the air cools to 80°C?

Description : A hot air balloon has a volume of 2800 m^3 at 99°C. What is the volume if the air cools to 80°C?

Last Answer : A hot air balloon has a volume of 2800 m3 at 99°C. What is the volume if the air cools to 80°C?

When we inflated a balloon the volume and pressure increases . does it violate the Boyle's law . explain?

Description : When we inflated a balloon the volume and pressure increases . does it violate the Boyle's law . explain?

Last Answer : No, this doesn't because P1V1 is a constant, which I think meansit needs to have the same quantity of gas, which blowing a balloonisn't. Boyle's law is only used when a fixed amount of gas is beingcompressed or uncompressed, changing only its volume andpressure.

When we inflated a balloon the volume and pressure increases . does it violate the boyles law . explain?

Description : When we inflated a balloon the volume and pressure increases . does it violate the boyles law . explain?

Last Answer : No, this doesn't because P1V1 is a constant, which I think meansit needs to have the same quantity of gas, which blowing a balloonisn't. Boyle's law is only used when a fixed amount of gas is beingcompressed or uncompressed, changing only its volume andpressure.

A balloon that contains 0.75 L of a gas at 25°C is cooled to –100°C. Calculate the new volume of the balloon.?

Description : A balloon that contains 0.75 L of a gas at 25°C is cooled to –100°C. Calculate the new volume of the balloon.?

Last Answer : dlId0

If you started with 100 grams of each of the materials below and they all vaporized inside of an inflatable balloon, which of them would produce the largest volume balloon, assuming they were all at the same temperature? w) water x) gasoline y) ethanol z) butane

Description : If you started with 100 grams of each of the materials below and they all vaporized inside of an inflatable balloon, which of them would produce the largest volume balloon, assuming they were all at the same temperature? w) water x) gasoline y) ethanol z) butane 

Last Answer : ANSWER: W -- WATER 

The radius of a circular plate increases by 2% on heating. If its radius is 10 cm before heating, find the approximate increase in its area.

Description : The radius of a circular plate increases by 2% on heating. If its radius is 10 cm before heating, find the approximate increase in its area.

Last Answer : The radius of a circular plate increases by 2% on heating. If its radius is 10 cm before heating, find the approximate increase in its area.

A hemispherical bowl is made of steel, 0.25 cm thick. The inner radius of the bowl is 5cm. Find the outer curved surface of the bowl. -Maths 9th

Description : A hemispherical bowl is made of steel, 0.25 cm thick. The inner radius of the bowl is 5cm. Find the outer curved surface of the bowl. -Maths 9th

Last Answer : Inner radius of hemispherical bowl = 5cm Thickness of the bowl = 0.25 cm Outer radius of hemispherical bowl = (5+0.25) cm = 5.25 cm Formula for outer CSA of hemispherical bowl = 2πr2, where r is radius of ... 22/7) (5.25)2 = 173.25 Therefore, the outer curved surface area of the bowl is 173.25 cm2.

Find the total surface area of a hemisphere of radius 10 cm -Maths 9th

Description : Find the total surface area of a hemisphere of radius 10 cm -Maths 9th

Last Answer : Radius of hemisphere, r = 10cm Formula: Total surface area of hemisphere = 3πr2 = 3×3.14×102 = 942 The total surface area of given hemisphere is 942 cm2.

Find the radius of a sphere whose surface area is 154 cm square. -Maths 9th

Description : Find the radius of a sphere whose surface area is 154 cm square. -Maths 9th

Last Answer : Let 'r' be the radius of sphere Surface area of sphere = 4 πr2 ⇒ 154 = 4 πr2 ⇒ 154 = 4 x 22/7 x r2 ⇒ r 2 = 154 x 7/4 x 22 = 49/4 ⇒ r = 7/2 cm = 3.5 cm

The surface area of a sphere of radius 5 cm -Maths 9th

Description : The surface area of a sphere of radius 5 cm -Maths 9th

Last Answer : Radius of the sphere (r1) = 5 cm Radius of the base of cone (r2) = 4 cm Let r сm be the height of the cone. Surface area of sphere = 4 πr2 ⇒ 4 π(5)2 = 100 π cm2 Curved surface area of cone = πrl = 4 πl ... ∴ Volume of cone = 1/3 πr2h = 1/3 x 22/7 x 42 x 3 = 352/7 cm3 = 50.29 cm3 (Approximately)

A spherical metal of radius 10 cm is melted and made into 1000 smaller spheres of equal sizes. In this process the surface area of the -Maths 9th

Description : A spherical metal of radius 10 cm is melted and made into 1000 smaller spheres of equal sizes. In this process the surface area of the -Maths 9th

Last Answer : Option (C) is correct. Solution: Let the radius of the small spheres be r' cm. Volume of metal remains the same in both cases. So, vol of the spherical metal of radius 10 cm = total ... Total Surface area of 1000 smaller spheres: 1000*4π12 = 4000π Hence, the surface area increased by 10 times.

The focal length of a plano-convex lens is 20 cm in air. Refractive index of glass is 1.5. Calculate (i) the radius of curvature of lens surface and (

Description : The focal length of a plano-convex lens is 20 cm in air. Refractive index of glass is 1.5. Calculate (i) the radius of curvature of lens surface and (

Last Answer : The focal length of a plano-convex lens is 20 cm in air. Refractive index of glass is 1.5. ... length when immersed in liquid of refractive index 1.6

Fig shows a small air bubble inside a glass sphere `(mu = 1.5)` of radius 10 cm. the bubble is 4.0 cm below the surface and is viewed normally from th

Description : Fig shows a small air bubble inside a glass sphere `(mu = 1.5)` of radius 10 cm. the bubble is 4.0 cm below the surface and is viewed normally from th

Last Answer : Fig shows a small air bubble inside a glass sphere `(mu = 1.5)` of radius 10 cm. the ... from the outside. Find the apparent depth of the bubble.

An object is placed `50 cm` from the surface of a glass sphere of radius `10 cm` along the diameter. Where will the final image be formed after refrac

Description : An object is placed `50 cm` from the surface of a glass sphere of radius `10 cm` along the diameter. Where will the final image be formed after refrac

Last Answer : An object is placed `50 cm` from the surface of a glass sphere of radius `10 cm` along the diameter. ... both the surfaces ? `mu` of glass `=1.5`.

What is the surface area of a sphere with a 3 cm radius?

Description : What is the surface area of a sphere with a 3 cm radius?

Last Answer : What is the surface area of a sphere with a 3 cm radius?

Find the ratio of surface area and volume of the sphere of unit radius. -Maths 9th

Description : Find the ratio of surface area and volume of the sphere of unit radius. -Maths 9th

Last Answer : Required ratio = 4πr2 / 4/3.πr3 = 3 x 4 x π x (1)2 / 4 x π x (1)3 = 3/1 (Since, r = 1) i.e., 3 : 1

For minimum curved surface area and given volume, the ration of the height and radius of base of a cone is :

Description : For minimum curved surface area and given volume, the ration of the height and radius of base of a cone is :

Last Answer : For minimum curved surface area and given volume, the ration of the height and radius of base of a cone is : A. ` ... : 1` C. `1 : 2` D. None of these

In case of laminar flow of fluid through a circular pipe, the (A) Shear stress over the cross-section is proportional to the distance from the surface of the pipe (B) Surface of velocity distribution is a paraboloid of revolution, whose volume equals half the volume of circumscribing cylinder (C) Velocity profile varies hyperbolically and the shear stress remains constant over the cross-section (D) Average flow occurs at a radial distance of 0.5 r from the centre of the pipe (r = pipe radius)

Description : In case of laminar flow of fluid through a circular pipe, the (A) Shear stress over the cross-section is proportional to the distance from the surface of the pipe (B) Surface of velocity distribution is a ... occurs at a radial distance of 0.5 r from the centre of the pipe (r = pipe radius)

Last Answer : (B) Surface of velocity distribution is a paraboloid of revolution, whose volume equals half the volume of circumscribing cylinder

Which of the following statements about septic shock are true? A. A circulating myocardial depressant factor may account for the cardiac dysfunction sometimes seen with shock due to sepsis or SIRS. B. A cardiac index (CI) of 6 liters per minute per square meter of body surface, a pulmonary capillary wedge pressure of 15 mm. Hg, and a systemic vascular resistance index (SVRI) of 800 dynes-sec/(cm 5-m 2) is a hemodynamic profile consistent with septic shock. C. An increase in SvO 2 in septic patients may be explained by the finding of anatomic arteriovenous shunts. D. Results of human trials employing antimediator therapy, such as antiendotoxin antibodies, IL-1 receptor antagonist, and tumor necrosis factor (TNF) antibodies, have confirmed animal studies that demonstrate a significant im

Description : Which of the following statements about septic shock are true? A. A circulating myocardial depressant factor may account for the cardiac dysfunction sometimes seen with shock due to sepsis or ... animal studies that demonstrate a significant improvement in survival with the use of such agents.

Last Answer : Answer: AB DISCUSSION: Shock due to sepsis or SIRS frequently manifests as a hyperdynamic cardiovascular response, consisting of an elevated CI and a decreased SVR or SVRI. Occasionally, ... been encouraging thus far in human clinical trials, despite the promising results from many animal studies

Two chords AB and CD of lengths 5 cm and 11 cm respectively of a circle are parallel to each other and are on opposite sides of its centre. If the A distance between AB and CD is 6 cm, find the radius of the circle. -Maths 9th

Description : Two chords AB and CD of lengths 5 cm and 11 cm respectively of a circle are parallel to each other and are on opposite sides of its centre. If the A distance between AB and CD is 6 cm, find the radius of the circle. -Maths 9th

Last Answer : Join OA and OC. Let the radius of the circle be r cm and O be the centre Draw OP⊥AB and OQ⊥CD. We know, OQ⊥CD, OP⊥AB and AB∥CD. Therefore, points P,O and Q are collinear. So, PQ=6 cm. Let OP=x. Then, ... r2=52+(2.5)2=25+6.25=31.25 ⇒r2=31.25⇒r=5.6 Hence, the radius of the circle is 5.6 cm

A glass sphere of radius 15 cm has a small bubble 6 cm from its centre. The bubble is viewed along a diameter of the sphere from the side on which it

Description : A glass sphere of radius 15 cm has a small bubble 6 cm from its centre. The bubble is viewed along a diameter of the sphere from the side on which it

Last Answer : A glass sphere of radius 15 cm has a small bubble 6 cm from its centre. The bubble is viewed along a ... be if the refractive index of glass is 1.5 ?

A metal wire of specific resistance `64xx10^(-6) Omega` m and length 1.98 cm has a resistance of `7 Omega`. Find its radius.

Description : A metal wire of specific resistance `64xx10^(-6) Omega` m and length 1.98 cm has a resistance of `7 Omega`. Find its radius.

Last Answer : A metal wire of specific resistance `64xx10^(-6) Omega` m and length 1.98 cm has a resistance of `7 Omega`. Find its radius.

the curved surface area of a cylinder is 154 cm. the total surface area of the cylinder is three times its curved surface area. find the volume of the cylinder. -Maths 9th

Description : the curved surface area of a cylinder is 154 cm. the total surface area of the cylinder is three times its curved surface area. find the volume of the cylinder. -Maths 9th

Last Answer : T.S.A = 3*154 = 462 cm² C.S.A = 154 cm² C.S.A = 2πrh T.S.A = 2πr(r+h) Now, In T.S.A = 2πrr + 2πrh 462 = 2πrr + 2πrh 462 = 2*22/7*r*r + 154 462 - 154 = 2*22/7*r*r 308*7/2*22 = r*r 49 = r*r R = 7 cm ... 7*h 154/44 = h 7/2 =h H = 3.5 cm or 7/2 cm Now volume = πrrh = 22/7 * 7* 7 *7/2 = 11*49 = 539 cm³

The volume of a certain rectangular solid is 8 cm^3. Its total surface area is 32 cm^2 and its three dimensions are in geometric progression. -Maths 9th

Description : The volume of a certain rectangular solid is 8 cm^3. Its total surface area is 32 cm^2 and its three dimensions are in geometric progression. -Maths 9th

Last Answer : (b) 32 Let the edges of the solid be a, ar, ar2. Then, Volume = a x ar x ar2 = a3r3 = (ar)3. Given (ar)3 = 8 ⇒ ar = 2 Also, surface area = 2(a x ar + ar x ar2 + a × ar2) = 2(a2r + ... Given, 2ar (a + ar + ar2) = 32 ⇒ 4(a + ar + ar2) = 32 ; Sum of lengths of all edges = 32.

If the lengths of a sides of a triangle are in the ratio 4 : 5 : 6 and the in-radius of the triangle is 3 cm, -Maths 9th

Description : If the lengths of a sides of a triangle are in the ratio 4 : 5 : 6 and the in-radius of the triangle is 3 cm, -Maths 9th

Last Answer : (b) 7.5 cm.Area of a triangle = \(rac{1}{2}\)x base x height= In-radius x semi-perimeter of the Δ \(\big[ ext{Using r =}rac{\Delta}{s}\big]\)Let the sides of triangle be 4x, 5x and 6x respectively. Given: In-radius = 3 ... x \(rac{15x}{2}\) = \(rac{6x}{2}\) x h ⇒ h = \(rac{45}{6}\) = 7.5 cm.