What is the value of 1/2 of 2/3 of 3/4 of 4/5 of 5/6 of 6/7 of 7/8 of 8/9 of 9/10 of 1000?

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

Replace the (?) with the correct mathematical signs to make the expression equal to 59.

18 ? 12 ? 4 ? 5 = 59

Can you find a seven digit number which describes itself. The first digit is the number of zeros in the number. The second digit is the number of ones in the number, etc. For example, in the number 21200, there are 2 zeros, 1 one, 2 twos, 0 threes and 0 fours.

If 5 cats catch 5 mice in 5 minutes, how long will it take one cat to catch a mouse?

Look at this sequence from top to bottom. What is the next number in the sequence?
1
11
21
1211
111221
312211

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

AB * C = DE - F = GH / I

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

Can you calculate the probability of getting a sum of six when a dice is thrown twice?

There once were seven dwarfs who were all brothers. They were all born two years apart. The youngest dwarf is seven years old. How old is his oldest brother?