A certain store sold pens for $0.35 each and pencils for $0.25 each. If a customer purchased both pens and pencils from the store for a total of $3.50, what total number of pens and pencils did the customer purchase?
Select
A) 8 B) 9 C) 10 D) 11 E) 12
Answer: Algebraically, the question looks like this: 2.5 = 0.35x + 0.25y There are six possible numbers of pens that fit that requirement:   1 pen: $0.35   2 pens: $0.70   3 pens: $1.05   4 pens: $1.40   5 pens: $1.75 balance can fetch 7 pencils for $0.25 each. That's 5 pens and 7 pencils for a total of 12 pens and pencils. Choice (12) is correct.
<result>E</result>
A certain store sold pens for $0.35 each and pencils for $0.25 each. If a customer purchased both pens and pencils from the store for a total of $3.50, what total number of pens and pencils did the customer purchase?