maths puzzle

puzzle

1.      What number should replace the question mark?             

Ans: 0.

Sol. Looking at lines of numbers from the top : 9×8 = 72; 72×8 = 576; 576×8 = 4608;

2.	What number should replace the question mark? Ans: 55. Sol. Each number indicates its position in the grid. 55 indicates row 5 columns 5.