Answer:
$73306.46
Explanation:
Compound interest = Principal(1+rate/n)^nt
If Kuley invested $20900 and compound interest rate of 7.8% per year for 7 years then,
Compound interest in 7 years =$20900(1+7.8/12)^12×7
=$20900×1.7233= $36016.97
After 3 years, Nabax would have 4 years left to make what kuley made in 7 years
Kuley made compound interest of $36016.97-$20900= $15116.97
Nabax will invest for 4 years at simple interest rate of 5.3%
Simple interest = principal×time×rate/100
We substitute to get his needed amount(principal)
$15116.97=Principal×4×5.3/100
$15116.97= 21.2Principal/100
Cross multiply to make principal subject of the formula:
Principal= 1511697/21.2
Principal = $73306.46
Therefore Nabax needs to invest $73306.46 to get the same amount of return that kuley got in 7 years
