From: gerald hodges
To: Teacher2Teacher Public Discussion
Subject: Re: Which way is correct?
Cliff, I just learned about "compatible numbers" which are numbers like 10 and 30 (i.e. they are easy to add, subtract, multiply or divide). 25 is a compatible number because it is easily associated with a quarter. Two quarters = 50 cents and two 25's = 50 so I would teach the 4th graders to round to the nearest compatible number for 25 and 26 to get a good estimate of the answer. Hope this is helpful. Gerald
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