SSC BOARD PAPERS IMPORTANT TOPICS COVERED FOR BOARD EXAM 2024

### A farmer borrows Rs. 1000 and agrees to repay with a total interest of Rs. 140 in 12 instalments, each instalment being less than the preceding instalment by Rs. 10. What should be his first instalment?

A farmer borrows Rs. 1000 and agrees to repay with a total interest of Rs. 140 in 12 instalments, each instalment being less than the preceding instalment by Rs. 10. What should be his first instalment?

Sol.

Since a farmer borrows Rs. 1000 and agrees to repay with a total interst of Rs. 140 12 instalments,
we can conclude that,
Sn = 1000 + 140 = Rs. 1140 with n = 12
Since he is paying each instalment being less than the preceding instalment by Rs. 10,
d = - 10.

Now, we need to find the first instalment,
i.e. a  = ?

 We Know that, Sn = n [2a + (n – 1) d 2 ∴ 1140 = 12 [2a + (12 – 1)(-10) 2 ∴ 1140 = 6 [2a – 110) ∴ 1140 = 2a – 110 6 ∴ 190 = 2a – 110 ∴ 190 + 110 = 2a ∴ 300 = 2a ∴ 300 = a 2 ∴ 150 = a ∴ a = 150

the amount of first instalment should be Rs. 150