We would apply the formula for determining compound interest. It is expressed as
A = P(1 + r/n)^nt
Where
A = total amount in the account after t years
r represents the interest rate
n represents the periodic interval at which it was compounded
P represents the principa or amount invested.
Considering Ruby's investment,
P = 850
r = 2 7/8 = 2.875/100 = 0.02875
n = 4 because it was compounded 4 times in a year
t = 17 years
Therefore,
A = 850(1 + 0.02875/4)^4 * 17
A = 850(1 + 0.0071875)^68
A = 1383.315
For Logan's investment,
P = 850
r = 2 3/8 = 2.375/100 = 0.02375
n = 12 because it was compounded 12 times in a year
t = 17 years
Therefore,
A = 850(1 + 0.02375/12)^12 * 17
A = 850(1 + 0.00197916667)^204
A = 1272.307
The difference between Ruby's return and Logan's return is
1383.315 - 1272.307 = 111.008
Rounding to the nearest dollar, it becomes $111
Therefore, Ruby has $111 in her account more than Logan