What goes up but never comes down?

By removing one matchstick and adding one matchstick, can you convert the word "ZOO" to an animal name?

Using Only Five 5's and any mathematical operator make sum as 37

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?

A mile-long train is moving at sixty miles an hour when it reaches a mile-long tunnel. How long does it take the entire train to pass through the tunnel?

What mathematical symbol can be put between 5 and 9, to get a number bigger than 5 and smaller than 9?

Replace each alphabet with the number (1-9) to make the below equation correct.

AB * C = DE - F = GH / I

Find the missing number in the sequence below:

Can you solve below mathematical equation?

2^1234 - 2^1233

In the following series, a set of numbers is progressing with a particular pattern. Can you deduce that pattern and find the missing set?

(2 + 6), (21 + 6), (58 + 6), (119 + 6), ___