Multiplication and Division of Fractions and Decimals Session 3 January 15, 2013
MEAP Review: Multi Digit Multiplication and Division of Whole Numbers and Decimals
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Transcript of MEAP Review: Multi Digit Multiplication and Division of Whole Numbers and Decimals
• ANSWERS
Dividing Difficult Large Numbers
31) 1719• 31 will not go into 1• 31 will not go into 17• 31 will go into 171
Dividing Difficult Large Numbers
31) 1719To figure what yourfirst number will becover the 1 in 31 &the 1 in 171.
Dividing Difficult Large Numbers
31) 1719Now ask how many3’s will go into 17.
Dividing Difficult Large Numbers
31) 1719Be sure to put thatnumber directly abovethe 1 not the 7.
5
Dividing Difficult Large Numbers
31) 1719Now multiply the 5x 31 and place it under the 171.
5
Dividing Difficult Large Numbers
31) 171931x5
5
155
155169
Dividing Difficult Large Numbers
31) 17195
155169
Now coverup the 1 in 31& the 9 in 169
Dividing Difficult Large Numbers
31) 17195
155169
Ask how many 3’s willgo into 16.
Dividing Difficult Large Numbers
31) 17195
155169
Place thatnumber nextto the 5 in your quotient.
5
Dividing Difficult Large Numbers
31) 17195
155169
Now multiply31 x 5.
5
Dividing Difficult Large Numbers
31) 17195
155169
5
15514
Subtract &your answeris 55 R14
Dividing Difficult Large Numbers
31) 17195
1551699
31X 5
5
155
155
Check It Using the Inverse of Division:
31 Multiply the divisor by the quotient. X 55 155+1550 1705+ 14 Add Remainder to the product1719 Your answer should math the original dividend
Multiplying and Dividing by powers of ten
MEAP REVIEW
10
100
1000
10100
5 7 4 8 23
ths101 ths
1001
ths1000
1s'1s'101001000000,10
What are the PLACE
VALUES of the digits in this number?
5 7 4 8 23
ths101 ths
1001
ths1000
1s'1s'101001000000,10
So that means
500 + 30 + 7 + + +104
1008
10002
5 7 4 8 23
ths101 ths
1001
ths1000
1s'1s'101001000000,10
The decimal point just separates the whole
numbers from the decimal fractions
5 7 4 8 23
ths101 ths
1001
ths1000
1s'1s'101001000000,10
What happens when I multiply this number by
10 ?
5 7 4 8 23
ths101 ths
1001
ths1000
1s'1s'101001000000,10
Each digits value will become 10 times bigger so the digits move LEFT into
the next column
537.482 x 10 = 5374.82
Multiplying by 10
It LOOKS like the decimal point moves one place to the right. (and that is how many teachers ask you to
think of it)
Multiplying by 10
Moving the digits one place to the LEFT looks the same as moving the decimal point one
place to the RIGHT.
5 7 4 8 23
5 7 4 8 23
More Multiplying and Dividing
Digits Move ( LOOKS LIKE )Decimal Point Moves
x10 One place to LEFT One place to RIGHT
x100 Two places to LEFT Two places to RIGHT
÷ 10 One place to RIGHT One place to LEFT
÷ 100 Two places to RIGHT Two places to LEFT
Thanks for watching.
I hope I haven’t LEFT you confused but I
thought we should get this RIGHT
To practice multiplying and dividing by multiples of ten, click on this website: http://www.bbc.co.uk/skillswise/numbers/wholenumbers/multiplication/multiply10and100/quiz.shtml
Get ready to boost these BAMZOOKI Zooks against the clock. Game on!Bamzooki Multiplying and Dividing
Quiz following the Investigation
Then….
• You’ll need all your mental maths skills to escape with the bio-rods in this exciting Mission 2110 game.
• Alien Game• Homework TIME• Multiplication and
Division Practice Handout