VOCABULARY CARDS

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VOCABULARY CARDS

• Multiplying and Dividing Integers

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You can think of multiplication as repeated
addition.
3 ? 2 2 2 2 6 and 3 ? (2) (2) (2)
(2) 6
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The patterns below suggest that when the signs of
integers are different, their product or quotient
is negative. The patterns also suggest that the
product or quotient of two negative integers is
positive.
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MULTIPLYING AND DIVIDING INTEGERS

Negative signs are
Your answer
positive
negative
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Example 1 Multiplying Integers
Find each product.
1A. 6 ? (5)
6 ? (5)
Both signs are negative, so the product is
positive.
30
1B. 4 ? 7
4 ? 7
The signs are different, so the product is
negative.
28
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Practice 1
Find each product.
1A. 2 ? (8)
2 ? (8)
Both signs are negative, so the product is
positive.
16
1B. 3 ? 5
3 ? 5
The signs are different, so the product is
negative.
15
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Example 2 Dividing Integers
Find each quotient.
2A. 35 (5)
The signs are different, so the quotient is
negative.
35 (-5)
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2B. 48 6
The signs are different, so the quotient is
negative.
48 (6)
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Practice 2
Find each quotient.
2A. 12 3
12 3
The signs are different, so the quotient is
negative.
4
2B. 25 (5)
The signs are the same, so the quotient is
positive.
25 5
5
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Example 3 Weather Application
At 700, the temperature was 14ºF. As a cold
front approached, the temperature dropped 6ºF per
hour over the next 4 hours. What was the
temperature at 1100?
Subtract the total number of degrees to find out
what the temperature was at 1100.
14 6 ? 4
Multiply 6 by 4 to find the total number of
degrees then subtract it from the original
temperature of 14ºF.
Use the order of operations. Multiply first. Then
subtract.
14 24
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The temperature at 1100 was 10?F.
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Practice 3
At 400, the train was 20 miles from the station.
The train traveled 18 miles away from the station
per hour over the next 6 hours. How far was the
train from the station at 1000?
Add the total number of miles from the train
station to find out how far the train was at
1000.
20 18 ? 6
Multiply 18 by 6 to find the total number of
miles then add it to the original distance of 20
miles.
Use the order of operations. Multiply first. Then
add.
20 108
The train was 128 miles from the station at 1000.
128
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Lesson Quiz
Use a number line to find the product. 1. 8 ? 2
Find each product or quotient. 2. 3 ? 5 ?
(2) 3. 75 5 4. 110 (2)
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55
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5. The temperature in Bar Harbor, Maine, was
3F. It then dropped 3 degrees per hour over
the next 3 hours. What was the temperature then?

12F