Goal: Think as mathematicians! Find a calculation shortcut by chunking, changing the form and connecting to math you know.
CthenC Google Slides Division Shortcut #1
CthenC Planner Division Shortcut #1
CthenC Meta Reflection Division Shortcut #1
Back to Contemplate then Calculate Tasks
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I’m wondering about why this one has decimals rather than fractions. The strategies I came up with all relate to the notion of the 0.5 as 1/2, and I don’t see 325 / 5 as “obvious” of a shortcut. So I’m wondering what the goal is with this problem using decimals.
The goal here is for math doers to this structurally by chunking, changing the form, and connecting to math they know. So students who “change the form” of 32.5 and/or 0.5 to a fraction equivalent to make the numbers easier to work are thinking structurally. Some may also change the form of the numeric expression, as you mentioned, to 325 / 5. Another approach might be to change the form of 32.5 to 30 + 2.5, and then divide each “chunk” by 0.5. or…
I could also imagine students connecting to what they know about division and asking themselves, “how many 1/2s are in 32.5?”.