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 Question from Susan, a parent: I'm a lawyer but evidently incredibly stupid at 4th grade math. . . .Question: cover a tabletop with 9 rows of square tiles with 9 squares in each row. How many tiles cover the tabletop? Then, the paper shows a 9x9 array and asks how it is used to solve the problem. My daughter wrote 9x9=81. The next question is "what are the products of the two smaller arrays?" ???? There are no other arrays - are we to make smaller arrays from the 9x9? how?

Susan,

Question: cover a tabletop with 9 rows of square tiles with 9 squares in each row.
How many tiles cover the tabletop?

OK, so far so good.

Then, the paper shows a 9x9 array and asks how it is used to solve the problem.

This is the sort of slowing-to-a-crawl that is all too common on school material. The idea is that unless a graphical model has been made of the problem the students do not "understand" it. (No matter how well they solve it, the response is "that is just a rote solution, they do not really understand it".) [Graphical thinking may be breathtakingly useful but it is NOT the only way.]

My daughter wrote 9x9=81.

Good. Please don't tell your daughter she does not understand it, she will be rightfully insulted!

The next question is "what are the products of the two smaller arrays?"

AAAARGH! Unless something has been omitted, I have no idea what this means - perhaps a 9x1 array along the top and a 1x9 array along the side? Even so, the plural "products" would be incorrect! This is also all too common - course material writers who cannot write clearly and expect students to read their minds.

Good hunting!
RD

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