Teacher2Teacher Q&A #522

Teachers' Lounge Discussion: Teaching subtraction

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From: raj

To: Teacher2Teacher Public Discussion
Date: 2001062506:55:48
Subject: subtraction from zeroes

aneasier way to subtract from zeroes is described here which eliminates the confusion of borrowing: ex: 24000 - 12345 --------- assume first 0 to be 10.subtrract 5 from this 10 and get 5.add 1 to 4 and make it 5.again assume next zero as 10 and subtract 5 from new 10.now add 1 to number '3' and make it 4.subtract this 4 from next zero which is assumed as zero.now add 1 to number '2'and make it '3'.subtract this 3 from number 4 and get 1.last number can be subtracted in usual manner.the process can be shown as follws: 2 4 0(10) 0(10) 0(10) - 1 2(+1) 3(+1) 4(+1) 5 ----------------------------------------------------------- 1 1 6 5 5 this method can also used to subtract any bigger number from lower number starting from unity which is asuumed a tens number.hope it works with your students.

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