In a row of boys, Rahul is 19th from top and Ajay is 21st from bottom. They interchange their position. Ajay now becomes 28th from bottom. Howmany total boys are there in the row?
If the first 10 terms and the last 10 terms of the given expression are interchanged in such a way that the first term is interchanged with the last, the second with the second last, the third with the third last and soon, what will the fifth term from the right be in the new arrangement?