Final answer:
To find the number of boys between M and Q, we use their positions from the end and from the front, then subtract from the total number of boys in the column. After calculating, we find that there are 10 boys between M and Q.option a is correct.
Step-by-step explanation:
To solve the problem, we need to first identify the positions of M and J in the column of boys. Since M is 8th from the end in a column of 30 boys, there are 7 boys after M. Similarly, because J is 12th from the front, there are 11 boys before J.
We can calculate the total number of boys up to J's position by adding J's position from the front (12) to the number of boys between J and Q (6), which equals 18. Now, subtracting this total from the entire column length (30) tells us that there are 12 boys after Q's position (30 - 18 = 12).
Adding the number of boys after M (7) to the number of boys after Q (12) shows us there are 19 boys outside of the M-Q segment. Since the total column is of 30 boys, we subtract 19 from 30 to find out the number of boys between M and Q, which is 11 (30 - 19 = 11). But we need to remove Q from this number, so there are 10 boys between M and Q.
Therefore, the answer to the question is option (a) 10 boys.