Routines for Reasoning Capturing Quantities – Multi-step decimal problem

Purpose Today we are learning how to find quantities and relationships in word problems and diagrams. We are going to build diagrams to help us understand a math problem dealing with fractions and decimals. We are going to talk to others to clarify our own thinking about the math problem.

Thinking Goals Think about a problem like a mathematician. Thinking Questions: What can be measured, what can be counted? What relationships can I find? How can I represent my thinking?

Jen went to the book fair. She bought 3 gel pens and a book Jen went to the book fair. She bought 3 gel pens and a book. The book cost $5.95. She gave the cashier $10.00. The cashier gave her 30 cents back. How much did one gel pen cost? What can be counted? What can be measured?

Jen went to the book fair. She bought 3 gel pens and a book Jen went to the book fair. She bought 3 gel pens and a book. The book cost $5.95. She gave the cashier $10.00. The cashier gave her 30 cents back. How much did one gel pen cost? “We can count/measure __________________.”

Jen went to the book fair. She bought 3 gel pens and a book Jen went to the book fair. She bought 3 gel pens and a book. The book cost $5.95. She gave the cashier $10.00. The cashier gave her 30 cents back. How much did one gel pen cost? What relationships between numbers to do you see?

Jen went to the book fair. She bought 3 gel pens and a book Jen went to the book fair. She bought 3 gel pens and a book. The book cost $5.95. She gave the cashier $10.00. The cashier gave her 30 cents back. How much did one gel pen cost? “One relationship I see is ________________.”

Jen went to the book fair. She bought 3 gel pens and a book Jen went to the book fair. She bought 3 gel pens and a book. The book cost $5.95. She gave the cashier $10.00. The cashier gave her 30 cents back. How much did one gel pen cost? What might a diagram of this problem look like?

Jen went to the book fair. She bought 3 gel pens and a book Jen went to the book fair. She bought 3 gel pens and a book. The book cost $5.95. She gave the cashier $10.00. The cashier gave her 30 cents back. How much did one gel pen cost? “We showed _____ by ______.” We used the ____ relationship to _____.”

Jen went to the book fair. She bought 3 gel pens and a book Jen went to the book fair. She bought 3 gel pens and a book. The book cost $5.95. She gave the cashier $10.00. The cashier gave her 30 cents back. How much did one gel pen cost? “We showed _____ by ______.” We used the ____ relationship to _____.”

Reflection Question: “Working Backwards on a math problem helps me to …”