In the following question, a matrix of certain characters is given. These characters follow a certain trend, row-wise or column-wise. Find out this trend and choose the missing character accordingly.
13
54
?
7
45
32
27
144
68
Answer: D. 4
In the first column, 13 + 7 x 2 = 27. In the second column, 54 + 45 x 2 = 144. Let the missing number in the third column be y. Then, y + 32 x 2 = 68 or y = 68 - 64 = 4.