Answer:
CI=P*(1 + R/100)^18
A=(CI + P) = P(1+R/100)^18
13500/P=1(100+R/100)^18
A/P=(100+R/100)^18
A/P=(100+R/100)^18
A=13500$ as (750 * 18)
(13500)/P=(1 +1.15/100)18
(13500)/P=(1+1.15/100)18
13500=((1.0115)^18
P=R$10989.02
Step-by-step explanation:
CI=Compound Interest
A=Amount
P=Principal.
Amplitude: 1/4 (= |a|)
Frequency: 1/2 (= |b|)
Period: 4pi (= 2pi/|b|)
She got back $2.50 hope this helped
