Description : n2 – 1 is divisible by 8, if n is (a) an integer (b) a natural number (c) an odd integer (d) an even integer
Last Answer : (c) an odd integer
Description : Is zero an odd or even number?
Last Answer : I think technically it’s even as it’s a multiple of 2 and therefore shares all the traits of even numbers.
Description : H.C.F of two prime numbers is (a) 1 (b) 0 (c) 3 (d) 2
Last Answer : (a) 1
Description : What's the longest known sequence of non-prime numbers?
Last Answer : My guess would be that such sequences grow in length with as number size gets larger. Prime numbers become increasing scarce as numbers get larger, making it more likely to find long sequences of primes.
Description : Two dice are thrown together. Find the probability that the sum of the numbers obtained is even a. 1/4 b. 1/6 c. 1/3 d. 1/2
Last Answer : d. 1/2
Description : Nine playing cards are numbered 2 to 10. A card is selected at random. What is the probability that the card will be an odd number? a. 1/9 b. 2/9 c. 4/9 d. 3/7
Last Answer : c. 4/9
Description : n Newton's Ring experiments , the diameter of bright rings is proportional to A. Square root of Odd Natural numbers B. Natural Number C. Even Natural Number D. Square root of natural number
Last Answer : B. Natural Number
Description : A dice is thrown once, what is the probability of getting a prime number? a. 1/3 b. 6/25 c. 1/2 d. 1/4
Last Answer : c. 1/2
Description : The prime factorisation of 96 is (a) 2 5 × 3 (b) 2 6 (c) 2 4 × 3 (d) 2 4 × 3 2
Last Answer : (a) 2 5 × 3
Description : The least number that is divisible by all the numbers from 1 to 5 is: (a) 70 (b) 60 (c) 80 (d) 90
Last Answer : (b) 60
Description : If a number x is chosen at random from the numbers -2, -1, 0 1, 2. What is the probability that x 2 < 2? a. 2/5 b. 3/5 c. 1/4 d. 4/7
Last Answer : b. 3/5
Description : A number is selected at random from first 50 natural numbers. Find the probability that it is a multiple of 3 and 4. a. 3/25 b. 2/25 c. 1/25 d. 13/50
Last Answer : b. 2/25
Description : If somebody choose two digit and three digit numbers and their difference is 989.What will be their sum? a) 1000 b)1010 c) 1006?
Last Answer : None of the above. Let x be the three digit number and y be the two digit number. x - y =989. x = 989 + y. x is obviously greater than 989 and less than 1000 (since it is three digits). Since y is a two digit number ... 989 + 10 = 999. We can't go any higher, so x =999 and y=10. x+y = 999+10 = 1009
Description : The sum or difference of of two irrational numbers is always (a) rational (b) irrational (c) rational or irrational (d) not determined
Last Answer : (b) irrational
Description : The sum of two irrational numbers is always (a) irrational (b) rational (c) rational or irrational (d) one
Last Answer : (a) irrational
Description : The product of two different irrational numbers is always (a) rational (b) irrational (c) both of above (d) none of above
Description : Now it was Ravi‘s turn. He rolled the dice. What is the probability that he got the sum of the two numbers appearing on the top face of the dice is greater than 8? a. 1 b. 5/36 c. 1/18 d. 5/18
Last Answer : d. 5/18
Description : Rahul got next chance. What is the probability that he got the sum of the two numbers appearing on the top face of the dice is equal to 7? a. 5/9 b. 5/36 c. 1/6 d. 0
Last Answer : c. 1/6
Description : Now it was Ravi‘s turn. He rolled the dice. What is the probability that he got the sum of the two numbers appearing on the top face of the dice is less than or equal to 12? a. 1 b. 5/36 c. 1/18 d. 0
Last Answer : a. 1
Description : Rahul got next chance. What is the probability that he got the sum of the two numbers appearing on the top face of the dice is 13? a. 1 b. 5/36 c. 1/18 d. 0
Last Answer : d. 0
Description : To the nearest 10%, what percentage of all numbers contain a 9?
Last Answer : You probably need to clarify that you mean what percentage of the set of all integers contains the digit 9'? Because there are an infinite number of numbers that don't contain that digit (and ... is also an infinite set of digits that does not. Maybe you need to restrict your range some more.
Description : Is the previous result of lotteries useful for predicting the numbers of a lottery ticket?
Last Answer : No. Every time is random.
Description : If 4! = 1x2x3x4 and is called 4 factorial, what is the sum of the numbers e.g. 4(?)= (1+2+3+4) called?
Last Answer : What’s wrong with the summation notation? It does just that. I don’t think there’s any other way of expressing it other than writing it out. [addition]: After more research, I found a formula where 1+2+3+4….+n= n*(n+1)/2 http://en.wikipedia.org/wiki/Triangular_number
Description : Brain Teaser - Indivisibility properties of sequence of numbers?
Last Answer : Mmmm homework =)
Description : Brain Teaser - Working with numbers that don't divide into one another?
Last Answer : 1) Write all of those numbers in the form: 2^k * m where m is an odd integer and k is a non-negative integer. Obviously m < 50. Since we have 25 odd numbers less than 50 if we pick 26 numbers between 1 and ... and hence n is at least 3 m. Hence k is larger than l. For (3) I should think a bit more.
Description : How are the British names for large numbers different from the American names?
Last Answer : 1,000,000,000 = billion in America, thousand million in England. 1,000,000,000,000 = trillion in America, billion in England. 1,000,000,000,000,000 = quadrillion in America, thousand billion in England. 1,000,000,000,000,000,000 = quintillion in America, trillion in England.
Description : Chapter 1 Real Numbers
Last Answer : Chapter 1 Real Numbers
Description : In a pocket of A, the ratio of Rs.1 coins, 50p coins and 25p coins can be expressed by three consecutive odd prime numbers that are in ascending order. The total value of coins in the bag is Rs 58. If the number of Rs.1 ... of coins in the pocket of A? A) Rs 68 B) Rs 43 C) Rs 75 D) Rs 82 E) NONE
Last Answer : Answer: D Since the ratio of the number of Rs. 1, 50p and 25p coins can be represented by 3 consecutive odd numbers that are prime in ascending order, the only possibility for the ratio is 3:5:7. Let the number of ... =100 7k+50 5k+25 3k=1025k (In above we find the value of k). ⇒ 8200p = Rs 82.
Description : When a number "n" is divided by 5, the remainder is 0 and when three times a number "n" is divided by 5 the remainder is what?
Last Answer : Since it’s not homework, the answer is 0.
Description : How many triangles will there be after n number of sequences?
Last Answer : I drew two more iterations of the pattern and added 9, then 12 more triangles. Your first two drawings showed 3 then 6. So the first 4 iterations go 3, 6, 9, 12 if that continues, it seems the pattern ... , 19, 31 and you'll have to give me a moment to come up with the formula for that sequence.
Description : If the universe turns out to be granular (meaning there is a smallest length and a smallest unit of time), is mathematics as it exists today a flawed, or even the wrong tool to describe reality?
Last Answer : That’s irrational. Sure I will agree will you.
Description : Are there any primes of the form 38^N+31?
Last Answer : The problem with question alike this is you can keep calculating ‘til the cows come home from jumping over the moon, but you’re never going to know for sure until you find a prime that fits the equation.
Description : (ak+1):(a+k)=(bk+1):(b+k+2)=(ck+2):(c+k+3)=n;a+b+c=12;k=multipkle of 2?
Last Answer : Homework. I don’t do it.
Description : For any natural numbern, 6 n – 5 n is always ends with (a) 4 (b) 3 (c) 2 (d) 1
Last Answer : (d) 1
Description : Is there any way to manipulate a sine function such that the amplitude when it is positive is larger than when it is negative?
Last Answer : Herp derp. I think I have an effective solution. Not quite what I was looking for, but. Just a slight vertical shift upwards. More of the wave will then lie above the x axis. If anyone has something better, do chime in!
Description : In real life we have situations such as: Rock > Scissors, Scissors > paper and Paper > Rock. Is there a type of math to deal with this?
Last Answer : answer:In Modular Arithmetic the numbers wrap around. That might be a good place to start to define the rules mathematically. As a kid we played rock, paper, scissors, bomb,. Symbol for bomb was fist with ... Bomb destroys rock, etc. .... Mod 4 Rock, paper,scissors, lizard, Spock would be Mod 5
Description : ABCD is a parallelogram with diagonal AC If a line XZ is drawn such that XZ ∥ AB, then BX/XC = ? (a) (AY/AC) (b) DZ/AZ (c) AZ/ZD (d) AC/AY Answer: (c) AZ/ZD 13. In the given figure, value of x (in cm) is (a) 5cm (b) 3.6 cm (c) 3.2 cm (d) 10 cm
Last Answer : (a) 5cm
Description : D and E are respectively the points on the sides AB and AC of a triangle ABC such that AD = 2 cm, BD = 3 cm, BC = 7.5 cm and DE || BC. Then, length of DE (in cm) is (a) 2.5 (b) 3 (c) 5 (d) 6
Last Answer : (b) 3
Description : O is a point on side PQ of a APQR such that PO = QO = RO, then (a) RS2 = PR × QR (b) PR2 + QR2 = PQ2 (c) QR2 = QO2 + RO2 (d) PO2 + RO2 = PR2
Last Answer : (b) PR2 + QR2 = PQ2
Description : Can you tender a one rupee note in such a manner that there shall be total 50 coins but none of them would be 2 paise coins?
Last Answer : Answer: 45 one paisa coins, 2 five paise coins, 2 ten paise coins, and 1 twenty-five paise coins.
Description : Two persons of masses 55 kg and 65 kg respectively, are at the opposite ends of a boat. The length of the boat is 3.0 m and weighs 100 kg. The 55 kg man walks up to the 65 kg man and sits with him. If the boat is in still water the centre of mass of the system shifts by
Last Answer : (4) zero
Description : In Newton's Ring experiments , the diameter of dark rings is proportional to A. Odd Natural numbers B. Natural Number C. Even Natural Number D. Square root of natural number
Last Answer : In Newton's Ring experiments , the diameter of dark rings is proportional to A. Odd Natural numbers B. Natural Number C. Even Natural Number D. Square root of natural number
Description : If the HCF of 65 and 117 is expressible in the form 65m – 117, then the value of m is (a) 4 (b) 2 (c) 1 (d) 3
Last Answer : (b) 2
Description : A flag pole 18 m high casts a shadow 9.6 m long. Then the distance of the top of the pole from the far end of the shadow is (a) 25.6 (b) 20.4 (c) 23.7 (d) 32.5
Last Answer : (b) 20.4
Description : The value of m obtained on solving equations : 2n + m =2n – m = √ a) 1/4 b) 0 c) 1/2 d) 3/4
Last Answer : b) 0
Description : If diameter of a wheel is 1.26 m, what the distance covered in 500 revolutions? (a) 1.38 km (b) 4.64 km (c) 2.46 km (d) 1.98 km
Last Answer : (d) 1.98 km
Description : If a circular grass lawn of 35 m in radius has a path 7 m wide running around it on the outside, then the area of the path is (a) 1450 m 2 (b) 1576 m 2 (c) 1694 m 2 (d) 3368 m 2
Last Answer : (c) 1694 m 2
Description : A goat is tied to one corner of a square plot of side 12 meter by a rope 7 meter long. Find the area it can graze? (a) 38.5 sq.m (b) 155 sq.m (c) 144 sq.m (d) 19.25 sq.m
Last Answer : (a) 38.5 sq.m
Description : Is the gcf of two odd numbers always even?
Last Answer : No not always as for example the GCF of 7 and 21 is 7