Problema Solution
Stephanie went to the Safeway store and bought 18 pounds of fruit consisting of apples and bananas. She paid $9 for the apples and $2.40 for the bananas. If the price per pound of the apples was 3 times that of the bananas, then how many pounds of each type of fruit did she buy?
Answer provided by our tutors
let
A = lbs of apples bought
a = the price of the apples per pound
B = lbs of bananas bought
b = the price of the bananas per pound
Stephanie went to the Safeway store and bought 18 pounds of fruit consisting of apples and bananas
A + B = 18
the price per pound of the apples was 3 times that of the bananas
a = 3b
she paid $9 for the apples and $2.40 for the bananas
a*A = 9 => a = 9/A
b*B = 2.40 => b = 2.40/B
if we plug this equations for a and b into a = 3b we have
9/A = 3*2.40/B
9B = 7.20A
by solving the system of equations
A + B = 18
9B = 7.20A
we have
A = 10 lbs
B = 8 lbs
click here to see the step by step solution of the system of equations
Stephanie bought 10 lbs of apples and 8 lbs of bananas.