Answer: account B had the greater capital. Step-by-step explanation: The formula for determining simple interest is expressed as I = PRT/100 Where I represents interest paid on the amount deposited. P represents the principal or amount deposited R represents interest rate T represents the duration in years. Considering account A, I = $15.75 T = 21 months = 21/12 = 1.75 years R = 3% Therefore, 15.75 = (P × 3 × 1.75)/100 15.75 = 0.0525P P = 15.75/0.0525 P = 300 Considering account B, I = $28 T = 21 months = 21/12 = 1.75 years R = 4% Therefore, 28 = (P × 4 × 1.75)/100 28 = 0.07P P = 28/0.07 P = $400 Therefore, account B had the greater capital.