Charis invested 140 . She earned a simple interest of 3% per year on the initial investment. If no money was added or removed from the investment, what was the amount of interest Charis received at the end of two years?

1 answer

To calculate the simple interest earned by Charis on her investment, we can use the formula for simple interest:

\[ I = P \cdot r \cdot t \]

where:

  • \(I\) is the interest,
  • \(P\) is the principal amount (the initial investment),
  • \(r\) is the interest rate (as a decimal),
  • \(t\) is the time in years.

Given:

  • \(P = 140\)
  • \(r = 3% = 0.03\)
  • \(t = 2\) years

Now, plug in the values into the formula:

\[ I = 140 \cdot 0.03 \cdot 2 \]

Calculating this step-by-step:

  1. Calculate \(0.03 \cdot 2\): \[ 0.03 \cdot 2 = 0.06 \]

  2. Now, calculate \(140 \cdot 0.06\): \[ 140 \cdot 0.06 = 8.4 \]

Thus, the amount of interest Charis received at the end of two years is:

\[ \boxed{8.40} \]