Which tank will fill first?

One absent-minded ancient philosopher forgot to wind up his only clock in the house. He had no radio, TV, telephone, internet, or any other means for telling time. So he travelled on foot to his friend's place a few miles down the straight desert road. He stayed at his friend's house for the night and when he came back home, he knew how to set his clock. How did he know?

If there are fifteen crows on a fence and the farmer shoots a third of them, how many crows are left?

If a wheel has 54 spokes, how many spaces are there between the spokes?

What occurs twice in a week, once in a year but never in a day?

How is a fly different from a mosquito?

Alex opened 24 presents
Jonah opened 8 presents
Clara opened 1 present

Can you find out how many presents were opened by Candy?

Can you arrange four 9's and use at most 2 math symbols, to make the total 100?

Why 1729 is a magic number? Answer Logically.

In a contest, four fruits (an apple, a banana, an orange, and a pear) have been placed in four closed boxes (one fruit per box). People may guess which fruit is in which box. 123 people participate in the contest. When the boxes are opened, it turns out that 43 people have guessed none of the fruits correctly, 39 people have guessed one fruit correctly, and 31 people have guessed two fruits correctly.
How many people have guessed three fruits correctly, and how many people have guessed four fruits correctly