Question

Roberto is charged 0.04% compound interest per day on his credit card purchase of $1200. Find the amount of interest owning after 30 days.

Answer 1

Given:

Assuming 360days in a year and proceeding

`P=\text{ \$1200 ; r=0.04\% ; }t=(1)/(12)\text{ years ; n=36}0`
`A=P(1+(r)/(n))^(nt)`
`A=1200(1+(0.04)/(360))^{360*(1)/(12)}`
`A=1200(1.0001)^(30)`
`A=1200(1.003)`
`A=1203.60`

Amount of interest owning after 30days is $3.60