1. Day 23 Multiplying Rational Numbers.notebook October 17, 2012
AIM: Multiplying Rational Numbers
Do Now
Basic Skills Quiz #3
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2. Day 23 Multiplying Rational Numbers.notebook October 17, 2012
Basic Skills Quiz #3
1.) Multiply and write your answer in simplest form.
3 1
2 3 5
4
2.) Complete the following decimal operation.
12.5 - 0.273
3.) What is the Greatest Common Factor of 12 and 30?
4.) Evaluate the following numeric expression using the order of
operations.
42 + 10 ÷ 2
5.) Round the following to the nearest inch.
72.35 inches
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3. Day 23 Multiplying Rational Numbers.notebook October 17, 2012
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4. Day 23 Multiplying Rational Numbers.notebook October 17, 2012
Anticipatory Set
On Core 1-4 (Pages 15-17 all)
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5. Day 23 Multiplying Rational Numbers.notebook October 17, 2012
Multiply Integers
3(-2) Means, three groups of (-2)
(-2) + (-2) + (-2)
­10 ­9 ­8 ­7 ­6 ­5 ­4 ­3 ­2 ­1 0
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6. Day 23 Multiplying Rational Numbers.notebook October 17, 2012
Multiply Integers
Use Commutative property to switch the
order
Mathematically this means we have four
groups of
+ + +
­6.0 ­5.5 ­5.0 ­4.5 ­4.0 ­3.5 ­3.0 ­2.5 ­2.0 ­1.5 ­1.0 ­0.5 0.0
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7. Day 23 Multiplying Rational Numbers.notebook October 17, 2012
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8. Day 23 Multiplying Rational Numbers.notebook October 17, 2012
Multiply Integers
Complete the pattern:
What do you notice when you multiply two
-5(3) = -15
integers with different signs?
-5(2) = -10
-5(1) = -5
-5(0) = 0 What do you notice when you multiply two
-5(-1) = 5 integers with the same signs?
-5(-2) = ___
-5(-3) = ___
-5(-4) = ___
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9. Day 23 Multiplying Rational Numbers.notebook October 17, 2012
Try each Product!
2(-12) = ____
(-7)(7.8) = ____
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10. Day 23 Multiplying Rational Numbers.notebook October 17, 2012
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11. Day 23 Multiplying Rational Numbers.notebook October 17, 2012
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12. Day 23 Multiplying Rational Numbers.notebook October 17, 2012
1.) A submarine is diving from the
surface of the water at a rate of 90 feet
per minute. What is the depth after 7
minutes?
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13. Day 23 Multiplying Rational Numbers.notebook October 17, 2012
2.) If I own 100 shares of Apple stock
and the price drops by $3 per share,
what is the change in my investment?
Write an expression.
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14. Day 23 Multiplying Rational Numbers.notebook October 17, 2012
SMART Response Activity
1 2
1.) -9 2.4 4.) -1 3 2 5
2.)
-2
3 ()-4
5 5.) 4 (-1.5)
3.) -4.1(-0.25) 6.) 4 (-2 ) 1
3
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15. Day 23 Multiplying Rational Numbers.notebook October 17, 2012
Multiplying Rational Numbers
Grade: «grade»
Subject: «subject»
Date: «date»
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16. Day 23 Multiplying Rational Numbers.notebook October 17, 2012
1
1.) -9 2.4
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17. Day 23 Multiplying Rational Numbers.notebook October 17, 2012
2
2.)
-2
3 () -4
5
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18. Day 23 Multiplying Rational Numbers.notebook October 17, 2012
3
3.) -4.1(-0.25)
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19. Day 23 Multiplying Rational Numbers.notebook October 17, 2012
4
1 2
4.) -1 3 2 5
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20. Day 23 Multiplying Rational Numbers.notebook October 17, 2012
5
5.) 4 (-1.5)
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21. Day 23 Multiplying Rational Numbers.notebook October 17, 2012
(-2 )
6
1
6.) 4 3
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22. Day 23 Multiplying Rational Numbers.notebook October 17, 2012
Before You Leave
Explain how adding rational numbers is
different than multiplying rational
numbers.
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23. Day 23 Multiplying Rational Numbers.notebook October 17, 2012
Homework
On Core Page 18
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