The principal on Marcus’ savings account is said to be 4 500 dollars
I think APR means annual percentage rate which is said to 5.3%.
Now, the question is, what is the simple interest that Marcus will earn after 30 weeks?
=> 30 weeks is equals to 6 months approximately.
Let’s solve first the annual interest
=> 4 500 dollars * .053 = 238.5 APR
=> 238.5 / 2 = 119.25
Thus, marcus will earn 119.25 dollars interest in 30 weeks.