Final answer:
To earn $50 of interest in 4 months at a 2.2% simple interest rate, you would need to invest approximately $6,818.18.
Step-by-step explanation:
To calculate how much you should invest at 2.2% simple interest to earn $50 interest in 4 months, we can use the simple interest formula I = PRT, where I is the interest earned, P is the principal amount invested, R is the rate of interest per time period, and T is the time period in years.
First, we need to convert the interest rate from a percentage to a decimal by dividing by 100, which gives us 0.022. Next, we convert the time duration from months to years. Since there are 12 months in a year, 4 months would be ⅓ or 0.3333... years.
Using the formula, we rewrite it to solve for P: P = I / (R × T). So, the principal P needed to earn $50 in 4 months at a 2.2% simple interest rate is:
P = $50 / (0.022 × 0.3333) = $50 / 0.007333 = $6,818.18 (rounded to two decimal places).
Therefore, you would need to invest approximately $6,818.18 to earn $50 of interest in 4 months at a simple interest rate of 2.2%.