You invest 1000 in an account that pays simple interest rate of 7% for 20 years

if the interest rate is anual, after 20 years the account would have $2400

Explanation:

(interest rate • $$$ invested • amount of time) + $$$ invested = $$$ after total amount of time

(0.07 • 1000 • 20) + 1000 = 2400