pls I need help

Question

1. John borrowed some money from the bank to buy a car and he promised to pay the money back, with interest at 6% per annum after 18 months. He paid £36000000 at the end of the 18 months. How much did he borrow. 

 

Answer 1

Let's say he borrowed £x. At simple interest rates the interest accumulated would be 6% times 1.5 = 9% after 18 months. So the amount of interest would be 0.09x pounds, where 0.09 is 9/100. Therefore the total amount would be x+0.09x=1.09x. If the amount he paid back after 18 months is £A then A=1.09x and x=A/1.09. If A=£36000000 (which is a LOT of money, especially for a car!) then he borrowed 36000000/1.09=£33,027,523. The interest alone would buy a number of cars!