Question

mohit borrowed a certain sum at 5% per annum compound interest and cleared this loan by paying 12600at the end of the first year and 17640 at the end of the second year. find the sum borrowed

Answer 1

Solution:-
Amount with interest paid at the end of first year = Rs. 12600.
A = P (1+r/100)ⁿ
Principal at the starting of the first year = 12600 = P (1+5?100)¹
12600 = 105P/100
P = (12600 × 100)/105
P = Rs 12000. 
Amount with interest paid at the end of second year = Rs 17640.
Principal at the starting of second year = 17640 = P (1+5/100)¹
17640 = 105P/100
P = (17640 × 100)/105
P = Rs 16800
Total sum borrowed = 12000 + 16800 = Rs 28800.
Answer.

Answer 2

Amount with interest paid at the end of first year = Rs. 12600.
Principal at the starting of the first year = 12600 
n= 1
A = P (1+r/100)ⁿ
= P (1+5/100)¹
12600 = 105 P/100
P = (12600 × 100)/105
P = Rs 12000. 
 
Amount with interest paid at the end of 2nd year = Rs 17640.
Principal at the starting of second year = 17640
= P (1+5/100)¹
17640 = 105 P/100
P = (17640 × 100)/105
P = Rs 16800
Total sum borrowed = 12000 + 16800 = Rs 28800.