Answer:
0,087792106 = rate
Explanation:
We need to calculate the interest of the investment
principal x (1 + rate)^time = value
replacing with the know values
24,000 x (1+rate)^2 = 28,399
28,399/24,000 = (1 + rate)^2
sqrt (28,399/24,000) -1 = rate
now we solve for the unknown value
0,087792106 = rate