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

Can you solve this tricky maths equation problem by replacing it? mark with the correct symbol?

19834 -----: 187
15921 -----: 153
17561 -----: 139
13734 -----: ???

There is a square of a particular number which when doubled, becomes 7 more than its quarter.

Can you find the number?

In a school, there are four subjects. Seventy percent of students study English, seventy five percent of students study Science, eighty five percent of students study Mathematics and eighty percent of students study Spanish.

Can you calculate the percentage of students that study all four subjects?

John was running from 40 thieves. John has got 3 gold boxes which weigh as 4kg, 2kg, and 1kg respectively. A witty man asked John to stay with him for seven days in exchange for 1kg gold per day. John needs to stay there for seven days and also do not want to give the witty man any advance. How can John pay for his seven days stay?

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?

What's a single-digit number with no value?

Find the value of "?" in the ball picture Riddle below:

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

If a zookeeper had 100 pairs of animals in her zoo, and two pairs of babies are born for each one of the original animals, then (sadly) 23 animals don’t survive, how many animals do you have left in total?