Math Corner - September 7, 2023 Edition
Date
9-7-2023
Question
Student Razor Q. Shark wants a new wardrobe for the Fall Semester. He makes 11 separate shopping trips during the semester to his favorite clothing store buying only shirts and/or shorts and nothing else on each shopping trip. Razor pays with his credit card on each shopping trip. At this store, each shirt costs $13 and each pair of shorts costs $5.
At the end of the semester, Razor reviews his credit card bills and discovers 12 charges from this store instead of 11 so Razor knows that one of them was charged to him in error. The amounts of each charge are:
$43, $102, $62, $57, $133, $97, $92, $47, $52, $123, $77, $36
Based on the value of the charges, which dollar amount charged was the amount charged in error?
COinS
Answer
$47 is not possible (There are no whole numbered ordered pairs where 13x + 5y = 47…the other 11 values are possible.)