Email me at this address if a comment is added after mine:Email me if a comment is added after mine

Privacy: Your email address will only be used for sending these notifications.

Anti-spam verification:

To avoid this verification in future, please log in or register.

3 Answers

+1 vote

Best answer

Answer is 11
First row is square of second row
Second row5*5=25, 7*7=49, therefore 11*11=121
and Second row + third row = fourth row
5+15=20, 7+13=20 and 11+9=20