In a row, Kumar is at 7th place from the left and Pawan is at 9th place from the right. When they interchange the positions Kumar becomes 11th from left. How many were seated in the row ?

Initialy from left 7th = kumar
from right 9th = pawan
Interchange kumar = 11th from left, from right kumar = 9th;
11+8 = 19;
8 is 1,2,3,4,5,6,7(pawan),8,9,10,11(kumar),12,13,14,15,16,17,18,19;
simply count the 9th place from right we will get total as 19.