Stuck? Start here. Read the steps, try the problem, then check your answer.
I can…
I can represent a real-world situation with a tape diagram or table and use decimal operations to solve it.
Key words
representation — A picture, diagram, table, or equation that shows the mathematics in a situation.
tape diagram — A rectangle cut into equal parts that helps you visualize how a total breaks apart.
tool — Anything you choose to help you see relationships and solve a problem — a table, a diagram, a graph.
ordered pair — Two numbers that go together, like a time and a number of trips, that you can plot as a point.
round trip — A complete journey from the start, to the destination, and back to the start.
Steps
A pile of coins is too big to count one at a time. About how many coins are in the pile?
I do not count every coin — I find a small stack I CAN count, about 10 coins.
Then I estimate how many stacks like that are in the pile. I count about 15.
15 stacks of about 10 is 15 × 10 = 150, so my estimate is about 150 coins — reasoned, not random.
Try it
Which statement best shows what this lesson means by "math is in my world"?
Check your answer
We visualize real problems, use tools to show relationships among quantities, and choose our tools strategically
The summary makes three claims: we visualize and represent problems, we use tools to show relationships among quantities, and we make strategic decisions about which tool to use.
Sentence starter
I know ___ because ___.
Goal: I can describe my tool using the words tape diagram, table, and this represents ___ .