Final answer:
To determine how long April can borrow $400 at an interest rate of 3% to pay $11 in interest, use the simple interest formula. The result is approximately 11/12 years, or about 11 months.
Step-by-step explanation:
April wants to borrow $400 and is willing to pay $11 in interest. Her father wants to charge her an interest rate of 3%. The question essentially asks how long it would take to accrue $11 in interest at this rate, which is a simple interest problem.
To find the time, we use the simple interest formula: Interest = Principal × Rate × Time. Here, the interest is $11, the principal is $400, and the rate is 3% per year, which can be written as 0.03. We will solve for time (T) as follows: $11 = $400 × 0.03 × T.
Dividing both sides by $400 × 0.03, we get: T = $11 / ($400 × 0.03). T = $11 / $12. T = 11/12 years.
Therefore, April can keep the money for 11/12 years, or approximately 0.9167 years, which is about 11 months.