Answer:
Interest earned at 3.9 percent rate is $31.2
Interest earned at 2 percent rate is $5.8
Step-by-step explanation:
A = P(1 + rt)
Where 'A' is the amount, 'r' is the rate and 't' is the time in years
When;
P = $1200
r = 3.9%
t = years
Then,
A = $1200(1 + 0.039())
A = $1200 + $31.2 = $1231.2
Interest = Amount - Principal
Interest earned at 3.9 percent rate is $1231.2 - $1200 = $31.2
When;
P = $580
r = 2%
t = years
Then,
A = $580(1 + 0.02())
A = $580 + $5.8 = $585.8
Interest earned = Amount - Principal
Interest earned at 2 percent rate = $585.8 - $580 = $5.8