Respuesta :
I=PRT/100
1. Make R (rate) subject
R/100= I/PT
2. Substitute and calculate
r/100= i/pt
r/100= 40/400 × 1
(40 is from 440-400.The interest)
r/100= 0.1
r/100×100= 0.1×100
r=10% (interest rate per year)
To confirm
I=PRT
I= 400×10/100×1
I= $40 (Interest)
Answer:
$40
Step-by-step explanation:
find Y
$400=x
$440=x+y
x+$40=x+y
$40=y
