Hello, I'm having a hard time fingering our this question. Not really sure what formula to use. Thanks in advance!

For a five year period, Ned deposited $800 each quarter into an account paying 5.6% annual interest compounded quarterly.

(a) How much money was in the account at the end of 5 years?

(b) How much interest was earned during the 5 year period?

To solve this problem, we can use the formula for compound interest:

A = P(1 + r/n)^(n*t)

Where:
A is the future value of the investment
P is the principal amount (the initial deposit)
r is the annual interest rate
n is the number of times interest is compounded per year
t is the number of years

In this case, we have:

P = $800 (since that's the quarterly deposit)
r = 5.6% (or 0.056 as a decimal)
n = 4 (since interest is compounded quarterly)
t = 5 (since we're looking at a 5-year period)

(a) To find the total amount of money in the account at the end of 5 years, we can substitute the values into the formula:

A = 800(1 + 0.056/4)^(4*5)

Calculating this, we get:

A ≈ $6,422.25

So, the amount of money in the account at the end of 5 years is approximately $6,422.25.

(b) To calculate the interest earned during the 5-year period, we can subtract the initial deposit (P) from the final amount (A):

Interest = A - P
Interest = $6,422.25 - ($800 * 4 * 5)

Calculating this, we get:

Interest ≈ $2,622.25

Therefore, the amount of interest earned during the 5-year period is approximately $2,622.25.