EM3SRB_G5_24A-24H.qxd
11/3/08
2:20 PM
Page 61
Whole Numbers
U.S. Traditional Long Division
U.S. Traditional long division is a method you can use to divide.
Share $845 among 3 people.
Step 1: Share the
2
4
5
38
6
2
Step 2: Trade 2
$100
s.
Ò Each person gets 2 $100 s.
Ò 2 $100 s each for 3 people
Ò 2 $100 s are left.
$100
s for 20 $10 s.
That makes 24 $10 s in all.
2
4
5
38
6
24
Ò 24 $10 s are to be shared.
Step 3: Share the
28
4
5
38
6
24
24
0
$10
s.
Ò Each person gets 8 $10 s.
Ò 8 $10 s each for 3 people
Ò 0 $10 s are left.
24E
EM3SRB_G5_24A-24H.qxd
11/12/08
11:57 AM
Page 62
Whole Numbers
Step 4: Share the
281
4
5
38
6
24
24
05
3
2
$1
s.
Ò Each person gets 1
$1
.
Ò5
$1
s are to be shared.
Ò1
$1
each for 3 people
Ò2
$1
s are left.
Each person gets $281; $2 is left over.
$845 / 3 ∑ $281 R$2
Divide.
1. $780 / 6 = ?
2. $973 / 4 = ?
3. $729 / 6 = ?
Check your answers on page 442.
24F
4. $828 / 8 = ?
EM3SRB_G5_24A-24H.qxd
11/5/08
10:56 AM
Page 63
Whole Numbers
U.S. traditional long division is not limited to dividing money.
9,427 / 7 ?
Think about the problem as dividing 9,427 into 7 equal shares.
Step 1: Start with the thousands.
Step 2: Trade 2 thousands
for 20 hundreds.
Share the hundreds.
Step 3: Trade 3 hundreds
for 30 tens.
Share the tens.
1
79
4
2
7
7
2
Ò Each share gets 1 thousand.
13
4
2
7
79
7
24
21
3
Ò Each share gets 3 hundreds.
134
4
2
7
79
7
24
21
32
28
4
Ò Each share gets 4 tens.
Ò 1 thousand 7 shares
Ò 2 thousands are left.
Ò 20 hundreds 4 hundreds
Ò 3 hundreds 7 shares
Ò 3 hundreds are left.
Ò 30 tens 2 tens
Ò 4 tens 7 shares
Ò 4 tens are left.
24G
EM3SRB_G5_24A-24H.qxd
11/12/08
11:58 AM
Page 64
Whole Numbers
continued
Step 4: Trade 4 tens for
40 ones.
Share the ones.
1346
4
2
7
79
7
24
21
32
28
47
42
5
Ò Each share gets 6 ones.
Ò 40 ones 7 ones
Ò 6 ones 7 shares
Ò 5 ones are left.
9,427 / 7 ∑ 1,346 R5
Divide.
1. 3,896 / 8 = ?
2. 36
,7
8
9
3. 56
,7
2
5
Check your answers on page 442.
24H
4. 4,304 / 4 = ?
EM3SRB_G5_24A-24H.qxd
11/3/08
2:10 PM
Page 65
Whole Numbers
U.S. Traditional Long Division: Multidigit Divisors
You can use U.S. traditional long division to divide by larger numbers.
Share $681 among 21 people.
Make a table of easy multiples of the divisor.
This can help you decide how many to share at each step.
1
21
2
* 21
* 21
3 * 21
4 * 21
5 * 21
6 * 21
8 * 21
10 * 21
42
Double 21.
63
Add 2 21 and 1 21.
84
Double 2 21.
105
Halve 10 21.
126
Double 3 21.
168
Double 4 21.
210
Move decimal point one place to the right.
Step 1: There are not enough [$100]s to share 21 ways,
so trade 6 [$100]s for 60 [$10]s.
Share the 68 [$10]s.
3
216
8
1
63
5
Ò
Ò
Ò
Ò
Each person gets 3 [$10]s.
There are 68 [$10]s to share.
3 [$10]s 21 shares
5 [$10]s are left.
Step 2: Trade the 5 [$10]s for 50 [$1]s.
Share the 51 [$1]s.
32
216
8
1
63
51
42
9
Ò Each person gets 2 [$1]s.
Ò 50 [$1]s 1 [$1]
Ò 2 [$1]s 21 shares
Ò 9 [$1]s are left.
$681 / 21 ∑ $32 R$9
24I
EM3SRB_G5_24A-24H.qxd
11/3/08
2:18 PM
Page 66
Whole Numbers
7720 / 25 ?
Make a table of easy multiples of the divisor.
1
* 25
2 * 25
3 * 25
4 * 25
5 * 25
6 * 25
8 * 25
10 * 25
25
50
Double 25.
75
Add 2 25 and 1 25.
100
Double 2 25.
125
Halve 10 25.
150
Double 3 25.
200
Double 4 25.
250
Move decimal point one place to the right.
Step 1: There are not enough
thousands to share
25 ways, so trade the
thousands for hundreds.
Share the hundreds.
Step 2: Trade the hundreds for tens.
Share the tens.
Step 3: Trade the tens for ones.
Share the ones.
3
257
7
2
0
75
2
Ò
Ò
Ò
Ò
Each share gets 3 hundreds.
77 hundreds
3 hundreds 25 shares
2 hundreds are left.
30 Ò There are not enough tens to share.
257
7
2
0
75
22 Ò 20 tens 2 tens
308
257
7
2
0
75
220
200
20
Ò Each share gets 8 ones.
Ò 22 tens 0 ones 220 ones
Ò 8 ones 25 shares
Ò 20 ones are left.
7720 / 25 ∑ 308 R20
Divide.
1. 359 / 57 = ?
2. 7,690 / 25 = ?
3. 156
,7
3
0
Check your answers on page 442.
24J
4. 525
,7
5
1