Download 3-7

Name
Reteaching
3-7
Dividing Decimals
When you divide by a decimal, you need to rewrite the dividend and the
divisor so that you are dividing by a whole number.
240 ÷ 80 = 3
Find 2.48 ! 0.8.
Step 1: Estimate. Use compatible numbers.
Step 2: Make the divisor a whole number.
Multiply the divisor AND the dividend by
the same power of 10.
0.8 QWWW
2.48
Place the decimal in the quotient.
.
8 QWWW
24.8
Step 3: Divide as you would with whole
numbers. Remember that sometimes you
may need to annex zeros to complete your
division.
Step 4: Compare the quotient with your
estimate.
0.8 10 8
2.48 10 24.8
3.1
8 QWWW
24.8
24
8
8
0
Since 3.1 is close to 3, the answer checks.
Find each quotient.
1. 0.2!"
1.5
"
Estimate:
Reteaching 3-7
Multiply dividend and divisor by what power of 10?
Place the decimal point in the quotient.
Divide. How many zeros do you need to annex?
Compare the quotient to your estimate.
Is the answer reasonable?
3. 0.4!"
9.6"
5. Draw a Picture Fernando used tenths grids
to draw this picture showing 1.6 ! 0.4 " 4.
Draw a picture to show 1.8 ! 0.6.
Write the quotient.
68
Topic 3
4. 0.75!"
0.3
"
© Pearson Education, Inc. 6
2. 0.6!"
0.36
"#
Name
Reteaching
3-7
Dividing Decimals
When you divide by a decimal, you need to rewrite the dividend and the
divisor so that you are dividing by a whole number.
240 ÷ 80 = 3
Find 2.48 ! 0.8.
Step 1: Estimate. Use compatible numbers.
0.8 QWWW
2.48
Step 2: Make the divisor a whole number.
Multiply the divisor AND the dividend by
the same power of 10.
Place the decimal in the quotient.
.
8 QWWW
24.8
Step 3: Divide as you would with whole
numbers. Remember that sometimes you
may need to annex zeros to complete your
division.
Step 4: Compare the quotient with your
estimate.
0.8 10 8
2.48 10 24.8
3.1
8 QWWW
24.8
24
8
8
0
Since 3.1 is close to 3, the answer checks.
Find each quotient.
7.5
1. 0.2!"
1.5
"
Estimate:
16 ÷ 2 = 8
Reteaching 3-7
Multiply dividend and divisor by what power of 10?
10
Place the decimal point in the quotient.
1
Yes, 7.5 is
Compare the quotient to your estimate.
close to 8.
Is the answer reasonable?
24
0.4
Divide. How many zeros do you need to annex?
2. 0.6!"
0.36
"#
3. 0.4!"
9.6"
4. 0.75!"
0.3
"
5. Draw a Picture Fernando used tenths grids
to draw this picture showing 1.6 ! 0.4 " 4.
Draw a picture to show 1.8 ! 0.6.
Write the quotient.
68
Topic 3
© Pearson Education, Inc. 6
0.6