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