A man borrows ₹ 8000 and agrees to repay with a total interest of ₹ 1360 in 12 monthly instalments. Each instalment being less than the preceding one by ₹ 40. Find the amount of the first and last instalment.

Given A man borrows = Rs. 8000
Repay with total interest = Rs 1360
In 12 months, thus n = 12
Thus, S₁₂ = 8000 + 1360 = 9360
Each installment being less than preceding one
Thus, d = – 40
We need to find “a”
Now, by using sum of n^th term of an A.P. we will find its sum

Thus, last installment t_n = 560