Three brothers Jacob, John, and James live in Mexico City. The product of the ages of these brothers is 175. Jacob and John are twins. How old is James?

How many pluses should we put between the digits of 987654321 to get a total of 99, and where?

Check out the number list below and find what number comes next in the sequence.

111 , 113 , 117 , 119 , 123 , 137 , ?

What will be the best approach to finding all the prime numbers less than 75 that leave an odd reminder when we divide them with 5?

How many people must be gathered together in a room, before you can be certain that there is a greater than 50/50 chance that at least two of them have the same birthday?

What three numbers, none of which is zero, give the same result whether they’re added or multiplied?

There is a straight highway. Four different villages lie on that highway. The distance between them is different. The third village is 60km away from the first village; the fourth is 40 km away from the second; the third is 10 km near to the fourth that it is to the second.

Can you calculate the distance between the fourth and the first village ?

Christina has four daughters, and each of her daughters has a brother. How many children does Christina have?

How many triangles are there in the picture below?

Can you think of any three-dimensional shape that comprises of exactly two surfaces?