In a row of 48 students facing North, Tinu is 15th from the left end. If Dinesh is 9th to the right of Tinu, what is Dinesh's position from the right end of the line?

Among five friends Pinky, Pooja, Prachi, Neha, and Payal: Pinky is older than only Pooja. Prachi is older than both Pooja and Pinky. Also, Prachi is younger than Neha, who is not the oldest. Who is the oldest?

Suraj ranked 17th from the bottom and 13th from the top in his class. How many students are there in his class?