Answer:
Sam would earn $18.00 from Joe.
Step-by-step explanation:
Joe borrowed $900 from Sam for six months. Sam charges simple interest at the rate of 4%.
In this question we have to find out Interest for 6 months with this formula.
I = Prt
I = Interest
P = Principal ( $900 )
r = rate of interest ( 4% ) in decimal
t = time in years. (1/2 yrs.)
first we convert 4% in decimal form.
4% =
= 0.04
I = 900 × 0.04 × 
I = 36 × 
I = $18.00
Sam would earn $18.00 from Joe.