Let’s solve each equivalent ratio problem step by step.
We know that two ratios are equivalent if they represent the same relationship — meaning you can multiply or divide both parts of one ratio by the same number to get the other.
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1) ___ : 8 = 5 : 2
We need to find what number goes with 8 to make it equal to 5:2.
Look at the second part: 2 → 8. That’s ×4.
So do the same to the first part: 5 × 4 =
20
✔ Answer:
20
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2) 3 : ___ = 21 : 35
First, simplify 21:35. Both divisible by 7 → 3:5
So 3 : ___ = 3 : 5 → missing number is
5
✔ Answer:
5
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3) 27 : 72 = 3 : ___
Simplify 27:72. Divide both by 9 → 3:8
So 3 : ___ = 3 : 8 → missing number is
8
✔ Answer:
8
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4) 6 : 7 = 36 : ___
6 → 36 is ×6
So 7 × 6 =
42
✔ Answer:
42
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5) 20 : 28 = 5 : ___
20 → 5 is ÷4
So 28 ÷ 4 =
7
✔ Answer:
7
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6) 30 : 54 = 5 : ___
30 → 5 is ÷6
54 ÷ 6 =
9
✔ Answer:
9
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7) 99 : ___ = 11 : 7
99 → 11 is ÷9
So ___ = 7 × 9 =
63
✔ Answer:
63
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8) 27 : 72 = 3 : ___
Same as #3 → 27÷9=3, 72÷9=8 →
8
✔ Answer:
8
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9) 7 : 12 = 28 : ___
7 → 28 is ×4
12 × 4 =
48
✔ Answer:
48
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10) 7 : 8 = 49 : ___
7 → 49 is ×7
8 × 7 =
56
✔ Answer:
56
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11) 9 : ___ = 36 : 16
36:16 simplifies? Divide both by 4 → 9:4
So 9 : ___ = 9 : 4 → missing is
4
✔ Answer:
4
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12) 18 : ___ = 6 : 7
18 → 6 is ÷3
So ___ = 7 × 3 =
21
✔ Answer:
21
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13) 9 : 10 = ___ : 20
10 → 20 is ×2
9 × 2 =
18
✔ Answer:
18
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14) 12 : 7 = ___ : 63
7 → 63 is ×9
12 × 9 =
108
✔ Answer:
108
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15) 72 : ___ = 12 : 11
72 → 12 is ÷6
So ___ = 11 × 6 =
66
✔ Answer:
66
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16) ___ : 30 = 4 : 3
3 → 30 is ×10
4 × 10 =
40
✔ Answer:
40
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17) 21 : 35 = 3 : ___
21 → 3 is ÷7
35 ÷ 7 =
5
✔ Answer:
5
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18) 8 : 3 = ___ : 12
3 → 12 is ×4
8 × 4 =
32
✔ Answer:
32
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19) 3 : 7 = 18 : ___
3 → 18 is ×6
7 × 6 =
42
✔ Answer:
42
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20) 16 : ___ = 2 : 3
16 → 2 is ÷8
So ___ = 3 × 8 =
24
✔ Answer:
24
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Final Answer:
1) 20
2) 5
3) 8
4) 42
5) 7
6) 9
7) 63
8) 8
9) 48
10) 56
11) 4
12) 21
13) 18
14) 108
15) 66
16) 40
17) 5
18) 32
19) 42
20) 24
Parent Tip: Review the logic above to help your child master the concept of ratio worksheet grade 7.
