Puzzles - Number puzzles

Answer

:

3

Explanation

:

Reading each column as a 3 digit number, moving from left to right, the columns follow the sequence of cube numbers of 5, 6 and 7.

Answer

:

13

Explanation

:

In each star, the central value equals the sum of the upper and lower digits on each star, subtracting the sum of the left and right hand digits.

Answer

:

6

Explanation

:

In each circle, double the numbers on the left hand side and put the result in the opposite segment on the right hand side.