so lets remember the formula for interest first.
#lightbulb
here it is A = P(1 + rt)
all we really have to do is plug in our rates, principles, and time into equation.
P = $800
t = 2 years
r = 6.5% or as a decimal 0.065
now lets look at our new equation that finally has numbers in it
A = 800[1 +(0.065)(2)] first lets take care of the 0.065 and 2 by multiplying them together. thus our new equation.
A = 800(1+ 0.13) then we add the 1 to the 0.13 and get 1.13
800(1.13) from here we just multiply and that equals 904
since we are looking for what is earned we take 904 and subtract 800 to get that answer. Here is the math.
904 - 800 = 104
he made 104 dollars in 2 years!
hope this is right.
have a good one:)
merry christmas:D