Which is faster, Heat or Cold ? Explain.

You order chicken wings at KFC in the boxes of 6, 9 and 20. What is the largest number of wings that you cannot obtain by buying in any combination of the boxes?

Look at the below sequence of letters and tell us what the next letter should be:

O T T F F S S ?

What is the next shape from answers A, B, C, and D figure?

There is a box full of marbles,
all but two are blue,
all but two are green,
and all but two are red.

How many marbles are in the box?

The ages of a father and son add up to 66.
The father's age is the son's age reversed.
How old could they be?
(3 possible solutions).

What does this mathematical rebus means ?

What is next number in the pattern below:

131 517 192 123 ?

When it is alive we sing, when it is dead we clap our hands. What is it?

Imagine a box with two cogwheels, one big with 24 teeth and one small with 8 teeth. The big one is firmly attached to the center of the box which means it does not turn or move while the small one rotates around the big one.

How many times do you think that the smaller wheel will turn compared to the box when it turns once around the big one?