FC: Inspector Joe and the Decimal Caper By Deborah Lyman | All images are clipart from microsoft.com
1: Joe (name has been changed to protect his identity) was born to be a number caper detective. When he was a just two years old, he was solving complex number equations in his sleep. As he started elementary school he was already proficient at calculus and algebra. In high school, he had taken every college level math course that was available. However, he did not want to sit behind a desk all day solving the mathematical problems of the world.
2: This is when Joe discovered an elite group of mathematician know as Math Inspectors Limited. These inspectors roamed the world looking for opportunities to solve math mysteries and dilemmas. Joe was recruited right out of high school and began his career. These are stories straight out of his top secret files. He has been given permission to share these files. All names and places have been changed in order to protect the identity of those involved.
3: The Case of the Miscalculation It started as a normal day off for Joe. He was headed to Jane's Grocery looking for some microwave dinners when he found Jessica in the parking lot staring at her receipt in confusion. Joe, being the trained detective, knew a math mystery when he saw one, so he approached Jessica and identified himself.
4: Jessica had purchased three items at the store: potatoes, apples and bananas. The potatoes were $2.25. the bananas were $1.57, and the apples were $3.16. She gave the cashier a $20 bill. The cashier gave her $14.98 in change. Joe sees right away that she did not get the right amount back. What did the cashier do wrong? Answer on page 9
5: The Missing Addend Inspector Joe was wondering the banks of the John's River looking for a case when he glanced James eating his lunch. He was counting his change over and over again. The inspector concluded at once that his services were needed. He carefully approached James and showed his badge. Immediately, James began to share his story.
6: James had purchased a sandwich, apple and a milk. The milk was $1.42 and the apple was $.93, but he could not remember how much he paid for the sandwich. He gave the cashier a $5 bill and received $1.14 in change. How much was the sandwich? Answer on page 9
7: Files of Missing Factors While meandering along Jake's Avenue, Inspector Joe noticed a Jeff in a local shop looking at a handful of trading cards in one hand and a $20 bill in the other. Inspector Joe had been having a lack of cases over the last week, so he pounced on the opportunity to offer assistance to a fellow human in need.
8: The store is running a special. If you buy 6 cards at $3.96, you will receive a 20% discount. Does Jeff have enough money to buy 6 cards and take advantage of the discount? If he does, how much change will he get back? You may need to round to the nearest cent. Answer on page 9
9: The Case of the Miscalculation - The cashier did not regroup the zeros. They simply subtracted from the zeros. The missing addend - The sandwich cost $1.51. Files of Missing Factors - Yes he has enough money. He will get $.99 back.