Question

In which of the following situations, do the lists of numbers involved form an AP? Give reasons for your answers.

The fee charged every month by a school from Classes I to XII, when the monthly fee for Class I is Rs 250, and it increases by Rs 50 for the next higher class.

Answer 1

The fee charged month by a school from I to XII is

250, (250 + 50), (250 + 2 × 50), (250 + 3 × 50),...

i.e., 250, 300, 350, 400,...

Which form an AP, with common difference (d) = 300 – 250 = 50