In a row of girls, Shilpa is eight from the left and Seema is seventeenth from the right, they interchange their positions, Shilpa becomes fourteenth from the left. How many girls are there in the row?

30

According to the question:

Shilpa is 8th from the left and Seema is 17th from the right. After they interchange the position Shilpa is 14th from left. So, according to the statement we can conclude that total number of students are 17 + 14 - 1 = 30 (as 1 position is being counted twice). Thus, total number of students are = 30