Question

In a row of children Parveen is 7th from the left, Babli is 4th from the right. When each of them exchange their positions, Parveen will be 15th from the left.Find the total number of children ?

Answer 1

In a row of children Parveen is 7th from the left, Babli is 4th from the right. When each of them exchange their positions, Parveen will be 15th from the left.Find the total number of children ?
       Solution:
                 total number of students = 15 + 3
                                                     = 18 students !!

Answer 2

let children be dots( . )          and left is indicted by (l) and right is indicated by (r)

.   .   .   .   .   .   .(parveen 7th(l))                                    .(babli 4th(r))    .    .    .
.   .   .   .   .   .   .(babli 7th(l))   .   .   .   .   .   .   .   .(parveen 15th(l))   .   .   .
Now,
parveen is 15th from left and 4th from right
Therefore,
total no of children = 15 + 3 = 18