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Mathematical Expression Editor
Consider the following division question.
(a)
Why is the figure above a division question? What are the groups? Objects
per group? What type of division is it?
(b)
Estimate the answer to the division question. Describe how you got your
estimate and why it makes sense.
(c)
Use the figure to find the answer to the division question.
(d)
Explain how the figure can be interpreted as .
(e)
Explain how the figure can also be interpreted as
(f)
Give at least two other ways to interpret the numbers in the division
question. What do all of these division questions have in common?
How would you calculate using long division? Use your work in the previous
problem to explain why it makes sense to move the decimal point around the way
that we do.
(a)
Draw a picture like the one in Problem 1 for the division problem . Don’t
solve in this step!
(b)
What other division problems can your picture illustrate? Give at least
three examples.
(c)
Use your picture to give an approximate answer to .
Phoebe thinks that the first step when dividing decimals is to remove the decimal
points, then use whole number division to calculate the answer, then put the decimal
point back in.
Carry out Phoebe’s procedure for . Does she get the right answer?
Carry out Phoebe’s procedure for . Does she get the right answer?
How could Phoebe use her procedure along with estimation to get the
correct answer for every example? Explain your thinking.
