Can you solve this amazing hard number series problem?
7, 8, 10, 12, 16, 18 ?

My cousin lives in one story house in Antarctica. His house is made the of-of sandstone. what is the color of stairs?

If I put in one canary per cage, I have one bird too many. If I put in two canaries per cage, I have one cage too many. How many cages and canaries do I have?

Below, you can see three complete equations and one incomplete. Based on the three complete ones, can you complete the incomplete one?

5 $ 4 $ 3 $ 9 = 4215
6 $ 9 $ 2 $ 6 = 3816
4 $ 7 $ 3 $ 3 = 1122
7 $ 2 $ 7 $ 4 = ____

What is the four-digit number in which the first digit is one-third the second, the third is the sum of the first two, and the last is three times the second?

Is the statement valid that it does not matter how much older a sibling is, eventually the younger one will be half as old as the older one?

John was drowned by he was not wet. How?

Analyze and find the missing item in the sequence:
16, 06, 68, 88, __, 98

Find the next number in the series

12, 20, 40, 72, 116, 172 ?

Suppose we lay down two cups in front of you. One of the cups is filled with tea and the other one with coffee. Now we ask you to take a spoonful of tea and mix it with the coffee. At this moment, the coffee cup has a mixture of tea and coffee. You have to take that mixture (spoonful) and add it back to the tea.

Can you now tell if the cup of coffee has more tea or the cup of tea has more coffee?