do now divide. 1. 24.5 ÷ 7 2. 50.4 ÷ 6 3. 19.2 ÷ (–2) 4. 128.1 ÷ 21 3.5 8.4 –9.6 course 2...
TRANSCRIPT
Do NowDivide.
1. 24.5 ÷ 7
2. 50.4 ÷ 6
3. 19.2 ÷ (–2)
4. 128.1 ÷ 21
3.5
8.4
–9.6
Course 2
3-5 Dividing Decimals and Integers by Decimals
6.1
Hwk: p 28
EQ How do I divide decimals and integers by decimals?
Course 2
3-5 Dividing Decimals and Integers by Decimals
M7N1.c Add, subtract, multiply, and divide positive and negative rational numbers; M7N1.d Solve problems usingrational numbers
Divide.
Additional Example 1A: Dividing Decimals by Decimals
8.28 ÷ 4.6
) 82.8461.
46–36 8
–36 8
0
8.28 ÷ 4.6
8
= 82.8 ÷ 46
Course 2
3-5 Dividing Decimals and Integers by Decimals
Divide.
Additional Example 1B: Dividing Decimals by Decimals
18.48 ÷ (–1.75)
18.48 ÷ (–1.75) = 1848 ÷ 175
)175 1848 . 001
–17598 0
0.5
–87 510 50
–10 50
0
18.48 ÷ (–1.75) = –10.56
6
The signs are different.
Course 2
3-5 Dividing Decimals and Integers by Decimals
Check It Out: Example 1A
Divide.
Insert Lesson Title Here
6.45 ÷ 0.5
) 64.5 51
5–14
–10
6.45 ÷ 0.5
2
4 5
.9
–4 50
= 64.5 ÷ 5
Course 2
3-5 Dividing Decimals and Integers by Decimals
Divide.
16.48 ÷ (–2.06)
16.48 ÷ (–2.06) = 1648 ÷ (206)
)1,6482068
–1 648
16.48 ÷ (–2.06) = –8
0
Check It Out: Example 1B
Course 2
3-5 Dividing Decimals and Integers by Decimals
Divide.
Additional Example 2A: Dividing Integers by Decimals
4 ÷ 1.25
4.00 ÷ 1.25 = 400 ÷ 125
)125 400 .03
–37525 0
–25 0
0Estimate4 ÷ 1 = 4
. 2
Course 2
3-5 Dividing Decimals and Integers by Decimals
Divide.
Additional Example 2B: Dividing Integers by Decimals
–24 ÷ (–2.5)
–24.0 ÷ (–2.5) = –240 ÷ (–25)
)25 2409
– 22515
.
.0
0
6
– 15 00
Estimate–24 ÷ (–3) = 8
Course 2
3-5 Dividing Decimals and Integers by Decimals
Divide.
Check It Out: Example 2A
6 ÷ 1.25
6.00 ÷ 1.25 = 600 ÷ 125
)125 600 .04
–500100 0
–100 00
Estimate6 ÷ 1 = 6
.8
Course 2
3-5 Dividing Decimals and Integers by Decimals
Divide.
Check It Out: Example 2B
–22 ÷ (–2.5)
–22.0 ÷ (–2.5) = –220 ÷ (–25)
)25 2208
–20020
.
.0
0
8
–20 00
Estimate–21 ÷ (–3) = 7
Course 2
3-5 Dividing Decimals and Integers by Decimals
Eric paid $229.25 to rent a car. The fee to rent the car was $32.75 per day. For how long did Eric rent the car?
Additional Example 3: Transportation Application
229.25 ÷ 32.75 = 22,925 ÷ 3,275
)3,275 22,9757
–22,9750
Eric rented the car for 7 days.
Course 2
3-5 Dividing Decimals and Integers by Decimals
Check It Out: Example 3
Jace took a trip in which he drove 350 miles. During the trip his truck used 12.5 gallons of gas. What was his truck’s gas mileage?
Insert Lesson Title Here
350.0 ÷ 12.5 = 3500 ÷ 125
)125 35002
–250100
8
0–1000
0
Jace’s truck’s gas mileage was 28 miles per gallon.
To calculate miles per gallon, divide the number of miles driven by the number of gallons of gas used.
Helpful Hint
Course 2
3-5 Dividing Decimals and Integers by Decimals
You Try
Divide. Estimate to check whether each answer is reasonable.
1. 78.2 ÷ 0.04
2. –9.72 ÷ 2.7
3. 18.88 ÷ 1.6
4. 19.5 ÷ 3.25
5. Jordan used 32.46 gallons of gas to drive his
van 584.28 miles. How many miles did Jordan get
per gallon?
–3.6
1,995
Insert Lesson Title Here
11.8
6
18
Course 2
3-5 Dividing Decimals and Integers by Decimals
You have two choicesA: start on your homework quietly B: open textbook to page 172 andstart working.