Respuesta :
Answer:
q =5.7% $21.204
Explanation:
The simple interest formula is
I = [tex]\frac{P*R*T}{100}[/tex]
Given that
I = Interest , T = time ; ;R is rate ; P = principal
The amount of Interest that John earned by July 1, 1993 is,
I = [tex]\frac{300*1* 8}{100}[/tex] = 72
Thus, the total amount in the account by July 1 1993
= $300 + $72= $372
We understand that he deposited this amount to earn interest at q rate
On July 1, 1998, John received $520. This means that his interest in the five years = $520-$372 = $148
Using the simple interest formula,
Interest = PRT/100
148 = [tex]\frac{520*5*q }{100}[/tex]
= 14,800 =2600q
q = [tex]\frac{14,800}{2,600}[/tex]
q = 5.69231%
Thus, rate = 5.7%
The interest that John earned between July 1, 1993 and July 1,1994 can be worked as
I = [tex]\frac{PRT}{100} = \frac{372*5.7*1}{100}[/tex]
= $21.204
