Shefali goes to a farmers' market every Saturday. Two
Saturdays ago, Shefali purchased 3 apples and
4 oranges for a total of $3.47. Last Saturday, she
purchased 12 oranges, but no apples, and spent $6.36.
Today, she only has one $10 bill. Given that none of
the prices have changed over the last 3 weeks, what is
the maximum number of apples she can purchase
today?
(Note: No sales tax is charged at this farmers' market.)
We can write equations for the situations described to obtain the price of each apple, A.
The price of 12 oranges, O:
12O=6.36
O=0.53
3 apples and 4 oranges cost $3.47:
3A+4O=3.47
3A+4(0.53)=3.47
3A+2.12=3.47
3A=1.35
A=0.45
With $10,
Ax=$10
(0.45)x=$10
x=22.2≈22