To: Teacher2Teacher Public Discussion
Subject: explain why we multipy to find the half of a recipe
I liked the posts by Gail instructing us to translate the "of" (eg 1/2 of 1/4) into multplication. But we get into a confusion of language usage of the word "divide" when we're trying to find the fraction of a fraction in a recipe. For example: if a recipe calls for 1/2 spoon of salt. How much salt do we need for half a recipe? In colloquial speech, one might say, "divide the recipe in half." Thus erroneous creating a division of fractions rather than multplication. How do we know when a word problem requires multiplication or division?
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