What is the riddle which can be asked all day with a different correct answer each time.

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

Use only one mathematical symbol and all numbers (0-9) to get a sum of 99

Can you make numbers like 24, using numbers 3,3,7 & 7 with any arithmetic operator?

13 decks of cards have been mixed. What is the minimum number of cards that must be taken out from the above-mixed cards to guarantee at least one 'four of a kind?

Name one eight-letter word with 'kst' in the middle, 'in' the beginning, 'and' at the end.?

Solve the below puzzle by replacing the question mark with the correct number.

3 6 12

4 8 16

5 10 ?

Use the digits from 1 up to 9 and make 100.

Follow the rules.
=> Each digit should be used only once.
=> You can only use addition.
=> For making a number, two single digits can be combined (for example, 4 and 2 can be combined to form 42 or 24)
=> A fraction can also be made by combining the two single digits (for example, 4 and 2 can be combined to form 4/2 or 2/4)

Question: how can we do this?

A California farmer owns a beautiful pear tree. He supplies the fruit to a nearby grocery store. The store owner calls the farmer to see how much fruit is available for him to buy. The farmer knows the main trunk has 24 branches. Each branch has exactly 12 boughs and each bough has exactly 6 twigs. Since each twig bears one piece of fruit, how many plums will the farmer be able to deliver?

Can you find out the missing number?

? 4 5 3 5

9 5 7 10 3