Question

A man arrange to pay off a debt of Rs3600by 40annual installments which forms an arithmetic series when 30 of the installments are paid he dies leaving one third of the debt unpaid find the value of the first installments

Answer 1

amount is 3600 paid in 40 installments the first installment amount is
3600/40 = 90 .
before he dies the total amount paid is 30 installments i.e 90 × 30 = 2700