Find the simple interest on a $400 investment made for 5 years at an interest rate of 7%/year. What is the accumulated amount?

Simple interest is a type of interest calculated solely on the principal amount invested. This means that no additional compound or accrued interest is taken into account when calculating simple interest. In this example, we are trying to calculate the simple interest on a $400 investment made for 5 years at an interest rate of 7%/year.

The formula for calculating Simple Interest (SI) is: SI = P x R x T where P stands for Principal Amount, R stands for Rate and T stands for Time (in years). Given these values in our question; SI = 400 x 0.07 x 5 = 140 dollars.

The accumulated amount after 5 years would then be equal to the original principal amount plus any accrued interests; therefore it will be equal to $400 + $140 = 540 dollars. It should also be noted that the same calculation can be done using online calculators such as https://www.calculatorsoup.com/calculators/financial/simple-interest-plus-principal-calculator.php which provide more convenience and accuracy than manually doing these calculations yourself