Explanation
Given:
Total strength of students = 45
Rank of a boy = 20th from one end.
∴ Rank from another end will be 45 - 20 + 1 = 26th
ACCORDING TO QUESTION :
Two boys joined, then total strength now = 47
Then, the rank dropped by one. This means one boy is ahead of him and another one is in behind.
His new rank from the end will be 26th + 1 = 27th
Hence, the rank of the boy is 27th.
