Question

You borrow $680 from your brother and agree to pay back $750 in 3 months. What simple interest rate will you pay?

Answer 1

hence rate interest r = 41.176%

Explanation:

The amount borrowed= $680

amount payed back = $750

therefore, interest incurred = 750-680= $70

time, t= 3 months = 3/12= 0.25 years

rate%, r

we know that SI=
`(PRT)/(100)`

70=
`(680*r\0.25)/(100)`

r=
`(7000)/(0.25*680) = 41.176`

hence rate interest r = 41.176%