Let’s solve each problem step by step. We’re looking for equivalent fractions — that means the two fractions represent the same value, even if they look different.
To find a missing number in an equivalent fraction, we can:
- Multiply or divide both numerator and denominator by the same number.
- Or use cross-multiplication: if a/b = c/d, then a×d = b×c.
We’ll go one by one.
---
1) 1/9 = ? / 27
Denominator went from 9 to 27 → multiplied by 3.
So multiply numerator by 3 too: 1 × 3 =
3
→ Answer:
3
---
2) 12/20 = 3 / ?
Numerator went from 12 to 3 → divided by 4.
So divide denominator by 4: 20 ÷ 4 =
5
→ Answer:
5
---
3) 3/5 = ? / 15
Denominator went from 5 to 15 → multiplied by 3.
Multiply numerator by 3: 3 × 3 =
9
→ Answer:
9
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4) 3/4 = ? / 28
Denominator: 4 → 28 → ×7
Numerator: 3 × 7 =
21
→ Answer:
21
---
5) 5/9 = 10 / ?
Numerator: 5 → 10 → ×2
Denominator: 9 × 2 =
18
→ Answer:
18
---
6) 8/20 = 2 / ?
Numerator: 8 → 2 → ÷4
Denominator: 20 ÷ 4 =
5
→ Answer:
5
---
7) 5/10 = ? / 80
Denominator: 10 → 80 → ×8
Numerator: 5 × 8 =
40
→ Answer:
40
---
8) 4/10 = ? / 5
Denominator: 10 → 5 → ÷2
Numerator: 4 ÷ 2 =
2
→ Answer:
2
---
9) 40/100 = 4 / ?
Numerator: 40 → 4 → ÷10
Denominator: 100 ÷ 10 =
10
→ Answer:
10
---
10) 3/? = 9/15
Numerator: 3 → 9 → ×3
So denominator must be: 15 ÷ 3 =
5
Check: 3/5 = 9/15? Yes, because 3×3=9, 5×3=15.
→ Answer:
5
---
11) 5/7 = ? / 35
Denominator: 7 → 35 → ×5
Numerator: 5 × 5 =
25
→ Answer:
25
---
12) 6/8 = ? / 4
Denominator: 8 → 4 → ÷2
Numerator: 6 ÷ 2 =
3
→ Answer:
3
---
13) 3/? = 9/24
Numerator: 3 → 9 → ×3
So denominator: 24 ÷ 3 =
8
Check: 3/8 = 9/24? 3×3=9, 8×3=24 → yes.
→ Answer:
8
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14) 3/10 = 12 / ?
Numerator: 3 → 12 → ×4
Denominator: 10 × 4 =
40
→ Answer:
40
---
15) 3/4 = ? / 44
Denominator: 4 → 44 → ×11
Numerator: 3 × 11 =
33
→ Answer:
33
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Final Answer:
1) 3
2) 5
3) 9
4) 21
5) 18
6) 5
7) 40
8) 2
9) 10
10) 5
11) 25
12) 3
13) 8
14) 40
15) 33
Parent Tip: Review the logic above to help your child master the concept of 4th grade math fraction worksheet.
