What number should replace the question mark in the grid?

2+3=1+4=5 .....

Answer: 5

Each number appearing in the far left column is the sum of the number of the last two columns appearing in the same row (ex. Top Row is 64251 5+1=6, Second Row is 83544 4+4=8, and so on)

In each row the first no is the sum of remaining nos divided by 2 I.e., 6=(4+2+5+1)/2 8=(3+5+4+4)/2 So. ?=(2+3+1+4)/2=5.

5 the difference b /w first column and 3rd column elkements is second column hence x-2=3 x=5

68-43 = 25, 68-54 = 14 83-30 = 53, 83-42 = 41 39-01 = 38, 39-22 = 17 9* -12 = 83, 9*-21=74 * = 5