VỀ CHÚNG TÔI

Chúng tôi lập ra blog này nhằm tạo 1 hệ thống các bài học môn Toán bằng Tiếng Anh , bao gồm video, listening scripts, từ vựng. Trong tương lai sẽ là các môn khoa học, kỹ năng sống. Chúng tôi rất mong nhận được những phản hồi, đóng góp lời dịch của các bạn. Cảm ơn bạn đã ghé qua blog này.

Wednesday 18 October 2017

BÀI 17 : MULTIPLYING DECIMALS.

XEM VIDEO TẠI ĐÂY

The following is a selected video from yourteacher.com  where you can browse over 450 complete math lessons with example videos interactive practice problems self tests and more try a complete lesson today at yourteacher.com

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.

0 comments:

Post a Comment