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| Math Central | Quandaries & Queries |
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My 3rd grader has been given a problem about mathematical arrays. Name two smaller arrays you can use to find the product. 7 x 6= ____ Obviously 7 x 6; 6 x 7 and 1 x 42; 42 x 1 and 2 x 21; 21 x 2 and 3 x 14; 14 x 3 are our choices, but I’m not really understanding what the question is asking. As my son said, “If we use 3 and 14, one of the numbers is smaller and one is larger." So Are we supposed to divide the problem into 2 separate arrays such as 2 (3x7) arrays to make 2 smaller arrays? I'm confused. Of course I have no textbook to resource. Charla |
Hi Charla,
As a former grade 3 teacher, I would have taught the students to break this up into 2 smaller multiplications or arrays.
7 x 6 is the same as
7 x 3 plus 7 x 3
It's easier for kids to remember 3 x 7 than 6 x 7.
We are always trying to break big numbers and operations into smaller ones which are then easier to solve.
Good luck,
Diane
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