The average interest gained from three accounts in one year is $913.224
<u>Explanation:</u>
Given:
Bank A:
Principal, P₁ = $250.67
Rate, r₁ = 12 %
Bank B:
Principal, P₂ = $765.13
Rate, r₂ = 7 %
Bank C:
Principal, P₃ = $28500.36
Rate, r₃ = 9 %
Interest from Bank A:

Interest from Bank B:

Interest from Bank C:

Average interest gained from three accounts in one year :

Therefore, average interest gained from three accounts in one year is $913.224
Answer: = 11.88
This is a 3 step / 4 show workings.
10.7 + Percentage increase = 11%
10.7 + (11% × 10.7) = 10.7 + 11% × 10.7
(1 + 11%) × 10.7 = (100% + 11%) × 10.7
111% × 10.7 = 111 ÷ 100 × 10.7
111 × 10.7 ÷ 100 = 1,187.7 ÷ 100
11.877 ≈ 11.88
The answer is 4i to this question
Hopefully I helped