Description : The diagonals of the three faces of a cuboid are x, y, z respectively. What is the volume of the cuboid ? -Maths 9th
Last Answer : answer:
Description : Three equal cubes are placed adjacently in a row. Find the ratio of total surface area of the new cuboid to that of the sum of the surface areas of the three cubes. -Maths 9th
Last Answer : Let each side of a cube = a cm Then surface area = 6a² cm² and surface area of 3 such cubes = 3 x 6a² = 18a² cm² By placing three cubes side by side we get a cuboid whose ... + 3a²] = 14 a² ∴ Ratio between their surface areas = 14a² : 18a² = 7 : 9
Description : Find the lateral surface area and total surface area of a cuboid of length 80 cm, breadth 40 cm and height 20 cm. -Maths 9th
Last Answer : Length of cuboid (l) = 80 cm Breadth (b) = 40 cm Height (h) = 20 cm (i) ∴ Lateral surface area = 2h(l + b) = 2 x 20(80 + 40) cm² = 40 x 120 = 4800 cm² (ii) Total surface area = 2(lb ... x 40 + 40 x 20 + 20 x 80) cm² = 2(3200 + 800 + 1600) cm² = 5600 x 2 = 11200 cm²
Description : Two cubes of side 2 cm each are joined end to end. Find the volume of the cuboid so formed. -Maths 9th
Last Answer : When two cubes of side 2 cm each are joined end to end then, Length (l) = (2 + 2) = 4cm Breadth (b) = 2 cm; Height (h) = 2 cm ∴ Volume of cuboid = lbh = 4 x 2 x 2 = 16 cm3
Description : Two cubes of edge 6 cm are joined to form a cuboid. Find the total surface area of the cuboid. -Maths 9th
Last Answer : When two cubes are joined end to end, then Length of the cuboid = 6 + 6 = 12 cm Breadth of the cuboid = 6 cm Height of the cuboid = 6 cm Total surface area of the cuboid = 2 (lb + bh + hi) = 2(12 x6 + 6×6 + 6×12) = 2(72 + 36 + 72) = 2(180) = 360 cm2
Description : The surface area of cuboid is 1792 sq cm. -Maths 9th
Last Answer : Let the height = x cm, then breadth = 2x cm length = 4x cm According to formula, 2(lb + bh + lh) = 1792 2(8x2 + 2x2 + 4x2) = 1792 28x2 = 1792 ⇒ x 2 = 1792/28 = 64 ⇒ x = 8 Length = 8 X 4 = 32 cm
Description : If V is the volume of a cuboid of dimensions l, -Maths 9th
Last Answer : V = lbh and S = 2(lb + bh + hl) Now RHS = 2/S(1/l + 1/b + 1/h) = 2/S(bh + hl + lb/lbh) = 2/S x S/2 x 1/V = 1/V = LHS.
Description : A cuboid shaped wooden block has 6 cm length, 4 cm breadth and 1 cm height. 17. Two faces measuring 4 cm x 1 cm are coloured in black. 18. Two faces measuring 6 cm x 1 cm are coloured in red. 19. Two faces ... colour on two sides and rest of the four sides having no colour ? (a)12 (b)10 (c)8 (d)4
Last Answer : Answer key : (c)
Description : A cuboid shaped wooden block has 6 cm length, 4 cm breadth and 1 cm height. 12. Two faces measuring 4 cm x 1 cm are coloured in black. 13. Two faces measuring 6 cm x 1 cm are coloured in red. 14. Two ... How many cubes will have 4 coloured sides and two non-coloured sides ? (a)8 (b)4 (c)16 (d)10
Last Answer : Answer key : (b)
Description : A cuboid shaped wooden block has 6 cm length, 4 cm breadth and 1 cm height. 7. Two faces measuring 4 cm x 1 cm are coloured in black. 8. Two faces measuring 6 cm x 1 cm are coloured in red. 9. Two faces measuring ... 1 cm(from 4 cm side). How many small cubes will be formed? (a)6 (b)12 (c)16 (d)24
Last Answer : Answer key : (d)
Description : A cuboid shaped wooden block has 6 cm length, 4 cm breadth and 1 cm height. 2. Two faces measuring 4 cm x 1 cm are coloured in black. 3. Two faces measuring 6 cm x 1 cm are coloured in red. 4. Two faces ... and black colours on at least one side of the cube will be formed? (a)16 (b)12 (c)10 (d)4
Description : A cylinder is within the cube touching all the vertical faces. A cone is inside the cylinder. If their heights are same with -Maths 9th
Description : If one of a parallelogram is twice of its adjacent angle , find the angles of the parallelogram . -Maths 9th
Last Answer : Let the two adjacent angles be x° and 2x° . In a parallelogram, sum of the adjacent angles are 180°. ∴ x + 2x = 180° ⇒ 3x = 180° ⇒ x = 60° Thus , the two adjacent angles are 120° and 60°. Hence, the angles of the parallelogram are 120°, 60°, 120° and 60°.
Description : If an angle of a parallelogram is two - third of its adjacent angle , then find the smallest angle of the parallelogram . -Maths 9th
Last Answer : In a parallelogram ABCD, Let ∠A be x and ∠B be 2x / 3 ∴ ∠A + ∠B = 180° ⇒ x + 2x / 3 = 180° ⇒ 5x / 3 = 180° ⇒ x° = 180° × 3 / 5 = 108° ∠A = 108° , ∠B = 2 / 3 × 108° = 72°
Description : In a parallelogram, show that the angle bisectors of two adjacent angles intersect at right angles. -Maths 9th
Last Answer : Given : A parallelogram ABCD such that the bisectors of adjacent angles A and B intersect at P. To prove : ∠APB = 90° Proof : Since ABCD is a | | gm ∴ AD | | BC ⇒ ∠A + ∠B = 180° [sum of consecutive interior ... 90° + ∠APB + ∠2 = 180° [ ∵ ∠1 + ∠2 = 90° from (i)] Hence, ∠APB = 90°
Description : The figure obtained by joining the mid-points of the adjacent sides of a rectangle of sides 8 cm and 6 cm, is -Maths 9th
Last Answer : Here, length of rectangle ABCD = 8 cm and breadth of rectangle ABCD = 6.cm Let E, F, G and H are the mid-points of the sides of rectangle ABCD, then EFGH is a rhombus.
Description : Construct a rectangle whose adjacent sides are of lengths 5 cm and 3.5 cm. -Maths 9th
Last Answer : We know that, each angle of a rectangle is right angle (i.e., 90°) and its opposite sides are equal and parallel. To construct a rectangle whose adjacent sides are of lengths 5 cm and 3.5 cm, use the ... AD and CD. Thus, ABCD is the required rectangle with adjacent sides of length 5 cm and 3.5 cm.
Last Answer : To construct a triangle ABC in which AB = 3.6 cm, AC = 3.0 cm and BC = 4. 8 cm, use the following steps. 1.Draw a line segment BC of length 4.8 cm. 2.From B, point A is at a distance of 3.6 ... 3.Joining BP, we obtain angle bisector of ∠B. 4.Flere, ∠ABC=39° Thus, ∠ABD = ∠DBC = 1/2 x 139° = 19.5°
Description : If two adjacent sides of a kite are 5cm and 7cm, find its perimeter. -Maths 9th
Last Answer : Solution :-
Description : Two adjacent angles of a ||gm are in the ratio 2:3. Find all the four angles of the parallelogram. -Maths 9th
Description : Prove that the figure formed by joining the mid-points of the adjacent sides of a quadrilateral is a parallelogram. -Maths 9th
Description : The lengths of two adjacent sides of a parallelogram are 17 cm and 12 cm. -Maths 9th
Last Answer : For △BCD: Let a = 17 cm, b = 12 cm, c = 25 cm So its semi-perimeter, s = (a + b + c)/2 = (17 + 12 + 25)/2 = 27 cm ∴ Area of △BCD = root under(√(s -a)(s - b)(s - c)) = ... △BCD = 2 x 90 = 180 cm2 Also, area of parallelogram ABCD = DC x AE ∴ 180 = 12 x AE ⇒ AE = 180/12 = 15 cm
Description : A cyclic parallelogram having unequal adjacent sides is necessarily a: -Maths 9th
Description : A rhombus has sides of length 1 and area 1/2 Find the angle between the two adjacent sides of the rhombus -Maths 9th
Description : The adjacent sides of a parallelogram are 2a and a. If the angle between them is 60°, then one of the diagonals of the parallelogram is -Maths 9th
Description : The adjacent sides of a rectangle are 16 cm and 8 cm. Find the area of the rectangle. -Maths 9th
Last Answer : area of rectangle is l×b 16×8 =128cm sq .area of rectangle is 128cm sq
Description : All the six faces of a cube of a cube are coloured with six different colours - black, brown, green, red, white and blue. 1. Red face is opposite to the black face. 2. Green face is between red and black ... face is in the bottom. Which face is opposite to green ? (a)Red (b)white (c) blue (d)brown
Last Answer : (c) blue
Description : All the six faces of a cube of a cube are coloured with six different colours - black, brown, green, red, white and blue. 1. Red face is opposite to the black face. 2. Green face is between red and black faces ... , brown, red (b) Blue, black, red, white (c) Red, black, blue, white (d) None of these
Last Answer : (a) Black, white, brown, red
Description : The diameter of the moon is approximately one fourth of the diameter of the earth. Find the ratio of their surface areas -Maths 9th
Last Answer : If diameter of earth is said d, then the diameter of moon will be d/4 (as per given statement) Radius of earth = d/2 Radius of moon = ½×d/4 = d/8 Surface area of moon = 4π(d/8)2 Surface area of earth = 4π(d/2)2 Ncert solutions class 9 chapter 13-6
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.
Description : The outer curved surface areas of the hemisphere and sphere are in ratio 2:9. find their ratio of their raddii -Maths 9th
Last Answer : This answer was deleted by our moderators...
Description : In a histogram, the areas of the rectangles are proportional -Maths 9th
Last Answer : No. It is true only when the class sizes are the same.
Description : Surface Areas and Volumes Class 9th Formulas -Maths 9th
Last Answer : Circle is the locus of all such points which are equidistant from a fixed point, this point is known as centre while distance of any point from centre defined as radius of circle. Here O is fixed ... the exterior angle is equal to the interior opposite angle. An isosceles trapezium is cyclic.
Description : NCERT Solutions for class 9 Maths Chapter 9 Areas of Parallelograms and Triangles Exercise 9.1 -Maths 9th
Last Answer : 1. Which of the following figures lie on the same base and between the same parallels. In such a case, write the common base and the two parallels. The figures (i), (iii), and (v) lie on the same base and between the same parallels.
Description : NCERT Solutions for class 9 Maths Chapter 9 Areas of Parallelograms and Triangles Exercise 9.2 -Maths 9th
Last Answer : 1. In the figure, ABCD is a parallelogram, AE ⊥ DC and CF ⊥ AD. If AB = 16 cm, AE = 8 cm and CF = 10 cm, find AD. We have AE ⊥ DC and AB = 16 cm ∵ AB = CD [opp. sides of parallelogram ABCD] ∴ ... sow wheat in (ΔPAQ) and pulses in [(ΔAPS) + (ΔQAR)] OR wheat in [(ΔAPS) + (ΔQAR)] and pulses in (ΔPAQ).
Description : NCERT Solutions for class 9 Maths Chapter 9 Areas of Parallelograms and Triangles Exercise 9.3 -Maths 9th
Last Answer : 1. In the figure, E is any point on median AD of a DABC. Show that ar (ABE) = ar (ACE). We have a ΔABC such that AD is a median. ∴ ar (ΔABD) = ar (ΔADC) ...(1) [∵ A median divides ... from both sides, we get [ar (ΔABD) - ar (ΔAOB)] = [ar (ΔABC) - ar (ΔAOB)] ⇒ ar (ΔAOD) = ar (ΔBOC)
Description : NCERT Solutions for class 9 Maths Chapter 9 Areas of Parallelograms and Triangles Exercise 9.4 -Maths 9th
Last Answer : 1. Parallelogram ABCD and rectangle ABEF are on the same base AB have equal areas. Show that the perimeter of the parallelogram is greater than that of the rectangle. We have a parallelogram ABCD and rectangle ABEF such that ar ( ... (BCED) = ar (ABMN) + ar (ACFG) [from (5)
Description : NCERT Solutions for class 9 Maths Chapter 13 Surface Areas and Volumes Exercise 13.1 -Maths 9th
Last Answer : 1. A plastic box 1.5 m long, 1.25 m wide and 65 cm deep is to be made. It is opened at the top. Ignoring the thickness of the plastic sheet, determine: (i) The area of the sheet required for making the box ... of a cylinder = 2πrh + 2πr2 = 2πr(h + r) Note: Unless it is mentioned assume π = (22/7)
Description : NCERT Solutions for class 9 Maths Chapter 13 Surface Areas and Volumes Exercise 13.2 -Maths 9th
Last Answer : 1. The curved surface area of a right circular cylinder of height 14 cm is 88 cm2. Find the diameter of the base of the cylinder. 2. It is required to make a closed cylindrical tank of height 1 m ... open from the top. ∴ Surface area of a penholder (cylinder) = [Lateral surface area] + [Base area]
Description : NCERT Solutions for class 9 Maths Chapter 13 Surface Areas and Volumes Exercise 13.3 -Maths 9th
Last Answer : 1. Diameter of the base of a cone is 10.5 cm and its slant height is 10 cm. Find its curved surface area. 2.Find the total surface area of a cone, if its slant height is 21 m and diameter of its base is 24 ... m2, what will be the cost of painting all these cones? (Use π = 3.14 and take √1.04= 1.02)
Description : NCERT Solutions for class 9 Maths Chapter 13 Surface Areas and Volumes Exercise 13.4 -Maths 9th
Last Answer : 1. Find the surface area of a sphere of radius: (i) 10.5 cm (ii) 5.6 cm (iii) 14 cm 2. Find the surface area of a sphere of diameter: (i) 14 cm (ii) 21 cm (iii) 3.5 m 3. Find the ... area of the sphere, (ii) curved surface area of the cylinder, (iii) ratio of the areas obtained in (i) and (ii).
Description : NCERT Solutions for class 9 Maths Chapter 13 Surface Areas and Volumes Exercise 13.5 -Maths 9th
Last Answer : 1. A matchbox measures 4 cm x 2.5 cm. x 1.5 cm. What will be the volume of a packet containing 12 such boxes ? 2. A cuboidal water tank is 6 m long, 5 m wide and 4.5 m deep. How many litres of ... 40 m wide is flowing at the rate of 2 km per hour. How much water will fall into the sea in a minute ?
Description : NCERT Solutions for class 9 Maths Chapter 13 Surface Areas and Volumes Exercise 13.6 -Maths 9th
Last Answer : 1. The circumference of the base of a cylindrical vessel is 132 cm and its height is 25 cm. How many litres of water can it hold ? (1000 cm3 = 1 l) . 2. The inner diameter of a cylindrical ... with soup to a height of 4 cm, how much soup the hospital has to prepare daily to serve 250 patients ?