Answer:
rate set by first complex bank is = 5.07 %
Explanation:
given data
simple interest = 6.4 %
investment time = 10 year
solution
we consider here first total interest on the amount $100 paid as simple interest is for 10 year will be
interest = $100 × 6.4% × 10
interest = $64
so future value will be = $100 + $64 = $164
so now we consider rate of interest = r
so that now we apply here future value formula
future value = investment × [tex](1+r)^{t}[/tex] ...............1
$164 = $100 × [tex](1+r)^{10}[/tex]
1.64 = [tex](1+r)^{10}[/tex]
solve it we get
r = 0.05071
so rate set by first complex bank is = 5.07 %