Question

I need help with please

Answer 1

Explanation:

1. Formula for simple interest,

`a = p(1 + rt)`

where

a = Final amount

p = Principal amount

r = annual interest rate

t = time in years

given p = 1250

r = 4.25/100 (r is a raw number, not percentage, so we need to divide 100 here to get the raw number)

t=4

Substitute values into formula to get a.

`a = 1250(1 + ((4.25)/(100))(4)) \\ = 1250(1 + 0.17) \\ = 1250(1.17) \\ = 1462.50dollars`

Let's use the simple interest to calculate Henry's final amount first.

p = 5000

r = 4.2/100

t = 4

`a = 5000(1 + ( (4.2)/(100) )(4)) \\ = 5000(1 + 0.168) \\ = 5000(1 .168) \\ = 5840 \: dollars`

To calculate the interest paid, just use the final amount minus the principal amount

`a - p = 5840 - 5000 \\ = 840dollars`

Now we will do the exact same method for Ingrid.

p = 5,000

r = 3.9/100

t = 6

`a = 5000(1 + ( (3.9)/(100) )(6)) \\ = 5000(1 + 0.234) \\ = 5000(1.234) \\ = 6170 \: dollars`

`a - p = 6170 - 5000 \\ = 1170dollars`

Difference in interest between 2 of them =

Interest of Ingrid Loan - Interest of Henry Loan

= 1170 - 840

= $330