Look at the attached picture and find out missing number on the grid.

Easy Number Grid Puzzle

The missing number is 60.

1 + 5 = 12
=> 1*2 + 5*2 = 12

2 + 10 = 24
=> 2*2 + 10*2 = 24

3 + 15 = 36
=> 3*2 + 15*2 = 36

Similarly,
5 + 25
=> 5*2 + 25*2 = 60

Discussion