From: Debra Muse
To: Teacher2Teacher Public Discussion
Subject: Commas in math
By breaking numbers into chunks of three, or in place value terms: in periods, makes it so easy to glance at a large number, count the corresponding periods and read it with ease. For example: 962,189,461,050 is read 962 then say the fourth period's name at the comma (and each subsequent period's name at its comma) ~ billion, 189 million, 461 thousand, 50. Beginning at the left, you read everything up to the comma as a number; at each comma you say that period's name. Voila. Even my third graders can read the above number!
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