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Wednesday, 18 October 2017

BÀI 17 : MULTIPLYING DECIMALS.

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To multiply decimals .
Sixteen  point one times two point four.
First  line up the numbers .
Then  multiplies though we were multiplying whole numbers .
So  we can think of this problem .
As  161 times 24.
Now multiplying 4 times 1 is 4.
 4 times 6 is 24 .
So  we bring down a 4 and carry the 2 .
4 times 1 is 4 plus 2 is 6.
Now starting a new row and beginning in the tens column .
We  have 2 times 1 which is 2.
2 times 6 which is 12 .
So  we bring down a 2 and carry the 1 .
2 times 1 is 2 plus 1 is 3.
Now  we add the rows together 4 plus 0 is 4 .
4 plus 2 is 6 .
6 plus 2 is 8 .
And we bring down the 3 so that we have 3860 for .
Our  final step is to determine where the decimal point goes in our final answer.
 Notice  that since there's one digit to the right of the decimal point
and 16 point one and one digit to the right of the decimal point in 2.4.
We have the total of two digits to the right of the decimal point in our original numbers.
 This  means we'll have two digits to the right of the decimal point in our final answer.

 So  16 point one times two point four is thirty eight point six four.

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