Question

A savings account has a 3% interest rate. (a) Complete the ratio table shown. Show your work. Deposit ($) 100 50 300 Interest ($) 12 (b) How much more interest would you have if you deposited $200 than if you deposited $150? Show your work.

Answer 1

Answer: Deposit($) Interest($) n years

100 12 4

50 6 4

300 36 4

200 24 4

150 18 4

b $ 6

Explanation:

Deposit($) Interest($) n

100 12 4

50 6 4

300 36 4

200 24 4

150 18 4

interest = principal x rate x time

i = p x r x n

12 = 100 x 3/100 x n

n = 12 x 100/100 x 3= 4 years

so n = 4 years

then calculate for others

I = 50 x 3/100 x 4 = $6

i = 300 x 3/100 x 4 = $36

I = 200 x 3/100 x 4 = $24

i = 150 x 3/100 x 4 = $ 18

b) thus $24 - $18 = $6

Answer 2

The amount of interest of the money invested in a savings account is calculated through the equation,
I = Prn
where I is the interest, P is the principal, r is the decimal equivalent of the given rate, and n is the number of years. In this item, we assume that n is equal to 1.
Solving for the interests,
$200: I = ($200)(0.03)(1) = $6
$150: I = ($150)(0.03)(1) = $4.5
The difference between the two calculated interests is $1.5.

Therefore, you could have earned $1.5 more if you invested $200 rather than $150.