Practice Session Decimal Subtraction
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Decimal Subtraction
Practice

Using Number Lines & Friendly Numbers

Problems
15
Strategy
Jump
Levels
3

✏️ Problem 1

🟢 Easy • One Jump
5.3 − 0.3
$5.30 − $0.30
💡 One-Jump Strategy
1 Subtract 0.3 to get to 5.0 (the friendly number!)
💰 Think: $5.30 minus 30 cents = exactly $5.00!
Number Line Model
5.0
5.3
− 0.3
✓ Answer
5.3 − 0.3 = 5.0

✏️ Problem 2

🟢 Easy • One Jump
8.6 − 0.6
$8.60 − $0.60
💡 One-Jump Strategy
1 Subtract 0.6 to get to 8.0 (the friendly number!)
💰 Think: $8.60 minus 60 cents = exactly $8.00!
Number Line Model
8.0
8.6
− 0.6
✓ Answer
8.6 − 0.6 = 8.0

✏️ Problem 3

🟢 Easy • Two Jumps
6.4 − 0.7
$6.40 − $0.70
💡 Two-Jump Strategy
1 First, subtract 0.4 to get to 6.0 (the friendly number!)
2 Still need to subtract 0.3 more (because 0.4 + 0.3 = 0.7)
3 6.0 − 0.3 = 5.7
💰 Think: Remove 40 cents to get $6, then remove 30 more cents!
Number Line Model
5.7
6.0
6.4
− 0.4
− 0.3
✓ Answer
6.4 − 0.7 = 5.7

✏️ Problem 4

🟢 Easy • Two Jumps
4.8 − 0.9
$4.80 − $0.90
💡 Two-Jump Strategy
1 First, subtract 0.8 to get to 4.0 (the friendly number!)
2 Still need to subtract 0.1 more (because 0.8 + 0.1 = 0.9)
3 4.0 − 0.1 = 3.9
💰 Think: Remove 80 cents to get $4, then remove 1 dime!
Number Line Model
3.9
4.0
4.8
− 0.8
− 0.1
✓ Answer
4.8 − 0.9 = 3.9

✏️ Problem 5

🟢 Easy • Two Jumps
7.2 − 0.5
$7.20 − $0.50
💡 Two-Jump Strategy
1 First, subtract 0.2 to get to 7.0 (the friendly number!)
2 Still need to subtract 0.3 more (because 0.2 + 0.3 = 0.5)
3 7.0 − 0.3 = 6.7
💰 Think: Remove 20 cents to get $7, then remove 30 more cents!
Number Line Model
6.7
7.0
7.2
− 0.2
− 0.3
✓ Answer
7.2 − 0.5 = 6.7

✏️ Problem 6

🟡 Medium • One Jump
3.25 − 0.25
$3.25 − $0.25
💡 One-Jump Strategy
1 Subtract 0.25 to get to 3.00 (the friendly number!)
💰 Think: $3.25 minus a quarter = exactly $3.00!
Number Line Model
3.00
3.25
− 0.25
✓ Answer
3.25 − 0.25 = 3.00

✏️ Problem 7

🟡 Medium • One Jump
9.47 − 0.47
$9.47 − $0.47
💡 One-Jump Strategy
1 Subtract 0.47 to get to 9.00 (the friendly number!)
💰 Think: $9.47 minus 47 cents = exactly $9.00!
Number Line Model
9.00
9.47
− 0.47
✓ Answer
9.47 − 0.47 = 9.00

✏️ Problem 8

🟡 Medium • Two Jumps
5.63 − 0.75
$5.63 − $0.75
💡 Two-Jump Strategy
1 First, subtract 0.63 to get to 5.00 (the friendly number!)
2 Still need to subtract 0.12 more (because 0.63 + 0.12 = 0.75)
3 5.00 − 0.12 = 4.88
💰 Think: Remove 63 cents to get $5, then remove 12 more cents!
Number Line Model
4.88
5.00
5.63
− 0.63
− 0.12
✓ Answer
5.63 − 0.75 = 4.88

✏️ Problem 9

🟡 Medium • Two Jumps
8.24 − 0.36
$8.24 − $0.36
💡 Two-Jump Strategy
1 First, subtract 0.24 to get to 8.00 (the friendly number!)
2 Still need to subtract 0.12 more (because 0.24 + 0.12 = 0.36)
3 8.00 − 0.12 = 7.88
💰 Think: Remove 24 cents to get $8, then remove 12 more cents!
Number Line Model
7.88
8.00
8.24
− 0.24
− 0.12
✓ Answer
8.24 − 0.36 = 7.88

✏️ Problem 10

🟡 Medium • Two Jumps
4.17 − 0.28
$4.17 − $0.28
💡 Two-Jump Strategy
1 First, subtract 0.17 to get to 4.00 (the friendly number!)
2 Still need to subtract 0.11 more (because 0.17 + 0.11 = 0.28)
3 4.00 − 0.11 = 3.89
💰 Think: Remove 17 cents to get $4, then remove 11 more cents!
Number Line Model
3.89
4.00
4.17
− 0.17
− 0.11
✓ Answer
4.17 − 0.28 = 3.89

✏️ Problem 11

🔴 Hard • Three Jumps
12.45 − 0.67
$12.45 − $0.67
💡 Multi-Jump Strategy
1 First, subtract 0.45 to get to 12.00 (the friendly number!)
2 Still need to subtract 0.22 more (because 0.45 + 0.22 = 0.67)
3 Break it up: subtract 0.20 to get 11.80, then 0.02 more
4 11.80 − 0.02 = 11.78
💰 Think: Remove 45 cents to get $12, then 2 dimes, then 2 pennies!
Number Line Model
11.78
11.80
12.00
12.45
− 0.45
− 0.20
− 0.02
✓ Answer
12.45 − 0.67 = 11.78

✏️ Problem 12

🔴 Hard • Three Jumps
15.38 − 0.52
$15.38 − $0.52
💡 Multi-Jump Strategy
1 First, subtract 0.38 to get to 15.00 (the friendly number!)
2 Still need to subtract 0.14 more (because 0.38 + 0.14 = 0.52)
3 Break it up: subtract 0.10 to get 14.90, then 0.04 more
4 14.90 − 0.04 = 14.86
💰 Think: Remove 38 cents to get $15, then a dime, then 4 cents!
Number Line Model
14.86
14.90
15.00
15.38
− 0.38
− 0.10
− 0.04
✓ Answer
15.38 − 0.52 = 14.86

✏️ Problem 13

🔴 Hard • Three Jumps
23.16 − 0.49
$23.16 − $0.49
💡 Multi-Jump Strategy
1 First, subtract 0.16 to get to 23.00 (the friendly number!)
2 Still need to subtract 0.33 more (because 0.16 + 0.33 = 0.49)
3 Break it up: subtract 0.30 to get 22.70, then 0.03 more
4 22.70 − 0.03 = 22.67
💰 Think: Remove 16 cents to get $23, then 3 dimes, then 3 pennies!
Number Line Model
22.67
22.70
23.00
23.16
− 0.16
− 0.30
− 0.03
✓ Answer
23.16 − 0.49 = 22.67

✏️ Problem 14

🔴 Hard • Three Jumps
31.72 − 0.85
$31.72 − $0.85
💡 Multi-Jump Strategy
1 First, subtract 0.72 to get to 31.00 (the friendly number!)
2 Still need to subtract 0.13 more (because 0.72 + 0.13 = 0.85)
3 Break it up: subtract 0.10 to get 30.90, then 0.03 more
4 30.90 − 0.03 = 30.87
💰 Think: Remove 72 cents to get $31, then a dime, then 3 pennies!
Number Line Model
30.87
30.90
31.00
31.72
− 0.72
− 0.10
− 0.03
✓ Answer
31.72 − 0.85 = 30.87

✏️ Problem 15

🔴 Hard • Three Jumps
45.09 − 0.34
$45.09 − $0.34
💡 Multi-Jump Strategy
1 First, subtract 0.09 to get to 45.00 (the friendly number!)
2 Still need to subtract 0.25 more (because 0.09 + 0.25 = 0.34)
3 Break it up: subtract 0.20 to get 44.80, then 0.05 more
4 44.80 − 0.05 = 44.75
💰 Think: Remove 9 cents to get $45, then 2 dimes, then a nickel!
Number Line Model
44.75
44.80
45.00
45.09
− 0.09
− 0.20
− 0.05
✓ Answer
45.09 − 0.34 = 44.75

📝 Key Takeaways

🎯 Find Friendly Numbers
Jump to the nearest whole number first. These "friendly numbers" make mental math easier!
💰 Think Money
Decimals are like dollars and cents. Use what you know about making change!
➡️ Break It Up
Big jumps can become smaller jumps. Subtract in parts that are easy to calculate.
📊 Use Number Lines
Visualizing jumps on a number line helps track your work and catch mistakes.