Rational and Irrational Numbers worksheet: Convert non-terminating recurring decimals to fractions.
Worksheet titled "Rational and Irrational Numbers" with 16 problems asking to express non-terminating recurring decimals as fractions in the form p/q.
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Step-by-step solution for: Irrational Numbers Worksheets - 15 Worksheets Library
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Show Answer Key & Explanations
Step-by-step solution for: Irrational Numbers Worksheets - 15 Worksheets Library
Let's solve each of these non-terminating recurring decimals and express them in the form $ \frac{p}{q} $, where $ p $ and $ q $ are integers and $ q \ne 0 $. We'll use algebraic methods to convert repeating decimals into fractions.
---
For a repeating decimal:
- Let $ x = $ the decimal.
- Multiply $ x $ by a power of 10 so that the repeating part aligns.
- Subtract the original $ x $ to eliminate the repeating part.
- Solve for $ x $.
We’ll go step-by-step.
---
Let $ x = 0.333\ldots $
Multiply both sides by 10:
$ 10x = 3.333\ldots $
Subtract:
$ 10x - x = 3.333\ldots - 0.333\ldots $
$ 9x = 3 $
$ x = \frac{3}{9} = \frac{1}{3} $
✔ Answer: $ \frac{1}{3} $
---
Let $ x = 1.444\ldots $
Multiply by 10:
$ 10x = 14.444\ldots $
Subtract:
$ 10x - x = 14.444\ldots - 1.444\ldots $
$ 9x = 13 $
$ x = \frac{13}{9} $
✔ Answer: $ \frac{13}{9} $
---
Let $ x = 0.575757\ldots $
Multiply by 100 (since two digits repeat):
$ 100x = 57.5757\ldots $
Subtract:
$ 100x - x = 57.5757\ldots - 0.5757\ldots $
$ 99x = 57 $
$ x = \frac{57}{99} = \frac{19}{33} $ (divide numerator and denominator by 3)
✔ Answer: $ \frac{19}{33} $
---
Let $ x = 0.001001001\ldots $
Multiply by 1000 (three digits repeat):
$ 1000x = 1.001001\ldots $
Subtract:
$ 1000x - x = 1.001001\ldots - 0.001001\ldots $
$ 999x = 1 $
$ x = \frac{1}{999} $
✔ Answer: $ \frac{1}{999} $
---
Let $ x = 0.535353\ldots $
Multiply by 100:
$ 100x = 53.5353\ldots $
Subtract:
$ 100x - x = 53.5353\ldots - 0.5353\ldots $
$ 99x = 53 $
$ x = \frac{53}{99} $
✔ Answer: $ \frac{53}{99} $
---
Let $ x = 2.939393\ldots $
Multiply by 100:
$ 100x = 293.9393\ldots $
Subtract:
$ 100x - x = 293.9393\ldots - 2.9393\ldots $
$ 99x = 291 $
$ x = \frac{291}{99} = \frac{97}{33} $ (divide by 3)
✔ Answer: $ \frac{97}{33} $
---
Let $ x = 18.484848\ldots $
Multiply by 100:
$ 100x = 1848.4848\ldots $
Subtract:
$ 100x - x = 1848.4848\ldots - 18.4848\ldots $
$ 99x = 1830 $
$ x = \frac{1830}{99} = \frac{610}{33} $ (divide numerator and denominator by 3)
✔ Answer: $ \frac{610}{33} $
---
Let $ x = 0.235235235\ldots $
Multiply by 1000:
$ 1000x = 235.235235\ldots $
Subtract:
$ 1000x - x = 235.235235\ldots - 0.235235\ldots $
$ 999x = 235 $
$ x = \frac{235}{999} $
Check if reducible: GCD(235, 999).
235 = 5 × 47
999 = 3³ × 37 → no common factors
✔ Answer: $ \frac{235}{999} $
---
This is $ 0.00323232\ldots $
Let $ x = 0.00323232\ldots $
The repeating part is "32", starting after two decimal places.
Multiply by 100 to shift past the non-repeating part:
$ 100x = 0.323232\ldots $
Now multiply by 100 again to get alignment:
$ 10000x = 32.323232\ldots $
Subtract:
$ 10000x - 100x = 32.3232\ldots - 0.3232\ldots $
$ 9900x = 32 $
$ x = \frac{32}{9900} = \frac{8}{2475} $ (divide numerator and denominator by 4)
✔ Answer: $ \frac{8}{2475} $
---
Let $ x = 0.999\ldots $
Multiply by 10:
$ 10x = 9.999\ldots $
Subtract:
$ 10x - x = 9.999\ldots - 0.999\ldots $
$ 9x = 9 $
$ x = 1 $
So $ 0.\overline{9} = 1 $
✔ Answer: $ \frac{1}{1} $ or simply $ 1 $
---
Let $ x = 2.4178178178\ldots $
Repeating part is "178" (3 digits), but it starts after one digit.
Let’s move the decimal:
Multiply by 10 to handle the non-repeating digit:
$ 10x = 24.178178178\ldots $
Now multiply by 1000 to align the repeating part:
$ 10000x = 24178.178178\ldots $
Subtract:
$ 10000x - 10x = 24178.178178\ldots - 24.178178\ldots $
$ 9990x = 24154 $
So $ x = \frac{24154}{9990} $
Simplify:
Divide numerator and denominator by 2:
$ \frac{12077}{4995} $
Check if reducible:
GCD(12077, 4995) — let's test.
Use Euclidean algorithm:
- 12077 ÷ 4995 ≈ 2 → 12077 - 2×4995 = 12077 - 9990 = 2087
- 4995 ÷ 2087 ≈ 2 → 4995 - 2×2087 = 4995 - 4174 = 821
- 2087 ÷ 821 ≈ 2 → 2087 - 1642 = 445
- 821 ÷ 445 ≈ 1 → 821 - 445 = 376
- 445 ÷ 376 ≈ 1 → 69
- 376 ÷ 69 ≈ 5 → 376 - 345 = 31
- 69 ÷ 31 ≈ 2 → 69 - 62 = 7
- 31 ÷ 7 ≈ 4 → 31 - 28 = 3
- 7 ÷ 3 = 2 → 1
- 3 ÷ 1 = 3 → remainder 0
GCD is 1 → already simplified.
✔ Answer: $ \frac{12077}{4995} $
---
Let $ x = 2.363636\ldots $
Multiply by 100:
$ 100x = 236.3636\ldots $
Subtract:
$ 100x - x = 236.3636\ldots - 2.3636\ldots $
$ 99x = 234 $
$ x = \frac{234}{99} = \frac{78}{33} = \frac{26}{11} $
✔ Answer: $ \frac{26}{11} $
---
Let $ x = 1.323323323\ldots $
Multiply by 1000:
$ 1000x = 1323.323323\ldots $
Subtract:
$ 1000x - x = 1323.323323\ldots - 1.323323\ldots $
$ 999x = 1322 $
$ x = \frac{1322}{999} $
Check simplification: GCD(1322, 999)
- 1322 ÷ 999 = 1 → remainder 323
- 999 ÷ 323 = 3 → 999 - 969 = 30
- 323 ÷ 30 = 10 → 323 - 300 = 23
- 30 ÷ 23 = 1 → 7
- 23 ÷ 7 = 3 → 2
- 7 ÷ 2 = 3 → 1
- 2 ÷ 1 = 2 → 0
GCD = 1 → irreducible
✔ Answer: $ \frac{1322}{999} $
---
Let $ x = 0.3178178178\ldots $
Repeating part "178" starts after first digit.
Multiply by 10:
$ 10x = 3.178178178\ldots $
Multiply by 1000:
$ 10000x = 3178.178178\ldots $
Subtract:
$ 10000x - 10x = 3178.178178\ldots - 3.178178\ldots $
$ 9990x = 3175 $
$ x = \frac{3175}{9990} $
Simplify: divide numerator and denominator by 5:
$ \frac{635}{1998} $
Check GCD(635, 1998):
- 635 = 5 × 127
- 1998 = 2 × 3³ × 37 → no common factors
✔ Answer: $ \frac{635}{1998} $
---
Let $ x = 0.4070707\ldots $
Multiply by 10:
$ 10x = 4.070707\ldots $
Multiply by 100:
$ 1000x = 407.070707\ldots $
Subtract:
$ 1000x - 10x = 407.0707\ldots - 4.0707\ldots $
$ 990x = 403 $
$ x = \frac{403}{990} $
Check GCD(403, 990):
- 403 = 13 × 31
- 990 = 2 × 3² × 5 × 11 → no common factors
✔ Answer: $ \frac{403}{990} $
---
Let $ x = 32.1235235235\ldots $
Repeating part "235" starts after one decimal place.
Multiply by 10:
$ 10x = 321.235235235\ldots $
Multiply by 1000:
$ 10000x = 321235.235235\ldots $
Subtract:
$ 10000x - 10x = 321235.235235\ldots - 321.235235\ldots $
$ 9990x = 320914 $
$ x = \frac{320914}{9990} $
Simplify:
Divide numerator and denominator by 2:
$ \frac{160457}{4995} $
Check if reducible: GCD(160457, 4995)
Use Euclidean algorithm:
- 160457 ÷ 4995 ≈ 32 → 4995 × 32 = 159840
- 160457 - 159840 = 617
- 4995 ÷ 617 ≈ 8 → 617 × 8 = 4936
- 4995 - 4936 = 59
- 617 ÷ 59 ≈ 10 → 590 → remainder 27
- 59 ÷ 27 = 2 → 54 → rem 5
- 27 ÷ 5 = 5 → 25 → rem 2
- 5 ÷ 2 = 2 → rem 1
- 2 ÷ 1 = 2 → rem 0 → GCD = 1
So fraction is simplified.
✔ Answer: $ \frac{160457}{4995} $
---
| Problem | Answer |
|--------|--------|
| 1) $ 0.\overline{3} $ | $ \frac{1}{3} $ |
| 2) $ 1.\overline{4} $ | $ \frac{13}{9} $ |
| 3) $ 0.\overline{57} $ | $ \frac{19}{33} $ |
| 4) $ 0.\overline{001} $ | $ \frac{1}{999} $ |
| 5) $ 0.\overline{53} $ | $ \frac{53}{99} $ |
| 6) $ 2.\overline{93} $ | $ \frac{97}{33} $ |
| 7) $ 18.\overline{48} $ | $ \frac{610}{33} $ |
| 8) $ 0.\overline{235} $ | $ \frac{235}{999} $ |
| 9) $ 0.00\overline{32} $ | $ \frac{8}{2475} $ |
| 10) $ 0.\overline{9} $ | $ 1 $ |
| 11) $ 2.4\overline{178} $ | $ \frac{12077}{4995} $ |
| 12) $ 2.\overline{36} $ | $ \frac{26}{11} $ |
| 13) $ 1.\overline{323} $ | $ \frac{1322}{999} $ |
| 14) $ 0.3\overline{178} $ | $ \frac{635}{1998} $ |
| 15) $ 0.4\overline{07} $ | $ \frac{403}{990} $ |
| 16) $ 32.1\overline{235} $ | $ \frac{160457}{4995} $ |
Let me know if you'd like these answers formatted as a printable sheet!
---
General Method:
For a repeating decimal:
- Let $ x = $ the decimal.
- Multiply $ x $ by a power of 10 so that the repeating part aligns.
- Subtract the original $ x $ to eliminate the repeating part.
- Solve for $ x $.
We’ll go step-by-step.
---
1) $ 0.\overline{3} $
Let $ x = 0.333\ldots $
Multiply both sides by 10:
$ 10x = 3.333\ldots $
Subtract:
$ 10x - x = 3.333\ldots - 0.333\ldots $
$ 9x = 3 $
$ x = \frac{3}{9} = \frac{1}{3} $
✔ Answer: $ \frac{1}{3} $
---
2) $ 1.\overline{4} $
Let $ x = 1.444\ldots $
Multiply by 10:
$ 10x = 14.444\ldots $
Subtract:
$ 10x - x = 14.444\ldots - 1.444\ldots $
$ 9x = 13 $
$ x = \frac{13}{9} $
✔ Answer: $ \frac{13}{9} $
---
3) $ 0.\overline{57} $
Let $ x = 0.575757\ldots $
Multiply by 100 (since two digits repeat):
$ 100x = 57.5757\ldots $
Subtract:
$ 100x - x = 57.5757\ldots - 0.5757\ldots $
$ 99x = 57 $
$ x = \frac{57}{99} = \frac{19}{33} $ (divide numerator and denominator by 3)
✔ Answer: $ \frac{19}{33} $
---
4) $ 0.\overline{001} $
Let $ x = 0.001001001\ldots $
Multiply by 1000 (three digits repeat):
$ 1000x = 1.001001\ldots $
Subtract:
$ 1000x - x = 1.001001\ldots - 0.001001\ldots $
$ 999x = 1 $
$ x = \frac{1}{999} $
✔ Answer: $ \frac{1}{999} $
---
5) $ 0.\overline{53} $
Let $ x = 0.535353\ldots $
Multiply by 100:
$ 100x = 53.5353\ldots $
Subtract:
$ 100x - x = 53.5353\ldots - 0.5353\ldots $
$ 99x = 53 $
$ x = \frac{53}{99} $
✔ Answer: $ \frac{53}{99} $
---
6) $ 2.\overline{93} $
Let $ x = 2.939393\ldots $
Multiply by 100:
$ 100x = 293.9393\ldots $
Subtract:
$ 100x - x = 293.9393\ldots - 2.9393\ldots $
$ 99x = 291 $
$ x = \frac{291}{99} = \frac{97}{33} $ (divide by 3)
✔ Answer: $ \frac{97}{33} $
---
7) $ 18.\overline{48} $
Let $ x = 18.484848\ldots $
Multiply by 100:
$ 100x = 1848.4848\ldots $
Subtract:
$ 100x - x = 1848.4848\ldots - 18.4848\ldots $
$ 99x = 1830 $
$ x = \frac{1830}{99} = \frac{610}{33} $ (divide numerator and denominator by 3)
✔ Answer: $ \frac{610}{33} $
---
8) $ 0.\overline{235} $
Let $ x = 0.235235235\ldots $
Multiply by 1000:
$ 1000x = 235.235235\ldots $
Subtract:
$ 1000x - x = 235.235235\ldots - 0.235235\ldots $
$ 999x = 235 $
$ x = \frac{235}{999} $
Check if reducible: GCD(235, 999).
235 = 5 × 47
999 = 3³ × 37 → no common factors
✔ Answer: $ \frac{235}{999} $
---
9) $ 0.00\overline{32} $
This is $ 0.00323232\ldots $
Let $ x = 0.00323232\ldots $
The repeating part is "32", starting after two decimal places.
Multiply by 100 to shift past the non-repeating part:
$ 100x = 0.323232\ldots $
Now multiply by 100 again to get alignment:
$ 10000x = 32.323232\ldots $
Subtract:
$ 10000x - 100x = 32.3232\ldots - 0.3232\ldots $
$ 9900x = 32 $
$ x = \frac{32}{9900} = \frac{8}{2475} $ (divide numerator and denominator by 4)
✔ Answer: $ \frac{8}{2475} $
---
10) $ 0.\overline{9} $
Let $ x = 0.999\ldots $
Multiply by 10:
$ 10x = 9.999\ldots $
Subtract:
$ 10x - x = 9.999\ldots - 0.999\ldots $
$ 9x = 9 $
$ x = 1 $
So $ 0.\overline{9} = 1 $
✔ Answer: $ \frac{1}{1} $ or simply $ 1 $
---
11) $ 2.4\overline{178} $
Let $ x = 2.4178178178\ldots $
Repeating part is "178" (3 digits), but it starts after one digit.
Let’s move the decimal:
Multiply by 10 to handle the non-repeating digit:
$ 10x = 24.178178178\ldots $
Now multiply by 1000 to align the repeating part:
$ 10000x = 24178.178178\ldots $
Subtract:
$ 10000x - 10x = 24178.178178\ldots - 24.178178\ldots $
$ 9990x = 24154 $
So $ x = \frac{24154}{9990} $
Simplify:
Divide numerator and denominator by 2:
$ \frac{12077}{4995} $
Check if reducible:
GCD(12077, 4995) — let's test.
Use Euclidean algorithm:
- 12077 ÷ 4995 ≈ 2 → 12077 - 2×4995 = 12077 - 9990 = 2087
- 4995 ÷ 2087 ≈ 2 → 4995 - 2×2087 = 4995 - 4174 = 821
- 2087 ÷ 821 ≈ 2 → 2087 - 1642 = 445
- 821 ÷ 445 ≈ 1 → 821 - 445 = 376
- 445 ÷ 376 ≈ 1 → 69
- 376 ÷ 69 ≈ 5 → 376 - 345 = 31
- 69 ÷ 31 ≈ 2 → 69 - 62 = 7
- 31 ÷ 7 ≈ 4 → 31 - 28 = 3
- 7 ÷ 3 = 2 → 1
- 3 ÷ 1 = 3 → remainder 0
GCD is 1 → already simplified.
✔ Answer: $ \frac{12077}{4995} $
---
12) $ 2.\overline{36} $
Let $ x = 2.363636\ldots $
Multiply by 100:
$ 100x = 236.3636\ldots $
Subtract:
$ 100x - x = 236.3636\ldots - 2.3636\ldots $
$ 99x = 234 $
$ x = \frac{234}{99} = \frac{78}{33} = \frac{26}{11} $
✔ Answer: $ \frac{26}{11} $
---
13) $ 1.\overline{323} $
Let $ x = 1.323323323\ldots $
Multiply by 1000:
$ 1000x = 1323.323323\ldots $
Subtract:
$ 1000x - x = 1323.323323\ldots - 1.323323\ldots $
$ 999x = 1322 $
$ x = \frac{1322}{999} $
Check simplification: GCD(1322, 999)
- 1322 ÷ 999 = 1 → remainder 323
- 999 ÷ 323 = 3 → 999 - 969 = 30
- 323 ÷ 30 = 10 → 323 - 300 = 23
- 30 ÷ 23 = 1 → 7
- 23 ÷ 7 = 3 → 2
- 7 ÷ 2 = 3 → 1
- 2 ÷ 1 = 2 → 0
GCD = 1 → irreducible
✔ Answer: $ \frac{1322}{999} $
---
14) $ 0.3\overline{178} $
Let $ x = 0.3178178178\ldots $
Repeating part "178" starts after first digit.
Multiply by 10:
$ 10x = 3.178178178\ldots $
Multiply by 1000:
$ 10000x = 3178.178178\ldots $
Subtract:
$ 10000x - 10x = 3178.178178\ldots - 3.178178\ldots $
$ 9990x = 3175 $
$ x = \frac{3175}{9990} $
Simplify: divide numerator and denominator by 5:
$ \frac{635}{1998} $
Check GCD(635, 1998):
- 635 = 5 × 127
- 1998 = 2 × 3³ × 37 → no common factors
✔ Answer: $ \frac{635}{1998} $
---
15) $ 0.4\overline{07} $
Let $ x = 0.4070707\ldots $
Multiply by 10:
$ 10x = 4.070707\ldots $
Multiply by 100:
$ 1000x = 407.070707\ldots $
Subtract:
$ 1000x - 10x = 407.0707\ldots - 4.0707\ldots $
$ 990x = 403 $
$ x = \frac{403}{990} $
Check GCD(403, 990):
- 403 = 13 × 31
- 990 = 2 × 3² × 5 × 11 → no common factors
✔ Answer: $ \frac{403}{990} $
---
16) $ 32.1\overline{235} $
Let $ x = 32.1235235235\ldots $
Repeating part "235" starts after one decimal place.
Multiply by 10:
$ 10x = 321.235235235\ldots $
Multiply by 1000:
$ 10000x = 321235.235235\ldots $
Subtract:
$ 10000x - 10x = 321235.235235\ldots - 321.235235\ldots $
$ 9990x = 320914 $
$ x = \frac{320914}{9990} $
Simplify:
Divide numerator and denominator by 2:
$ \frac{160457}{4995} $
Check if reducible: GCD(160457, 4995)
Use Euclidean algorithm:
- 160457 ÷ 4995 ≈ 32 → 4995 × 32 = 159840
- 160457 - 159840 = 617
- 4995 ÷ 617 ≈ 8 → 617 × 8 = 4936
- 4995 - 4936 = 59
- 617 ÷ 59 ≈ 10 → 590 → remainder 27
- 59 ÷ 27 = 2 → 54 → rem 5
- 27 ÷ 5 = 5 → 25 → rem 2
- 5 ÷ 2 = 2 → rem 1
- 2 ÷ 1 = 2 → rem 0 → GCD = 1
So fraction is simplified.
✔ Answer: $ \frac{160457}{4995} $
---
✔ Final Answers:
| Problem | Answer |
|--------|--------|
| 1) $ 0.\overline{3} $ | $ \frac{1}{3} $ |
| 2) $ 1.\overline{4} $ | $ \frac{13}{9} $ |
| 3) $ 0.\overline{57} $ | $ \frac{19}{33} $ |
| 4) $ 0.\overline{001} $ | $ \frac{1}{999} $ |
| 5) $ 0.\overline{53} $ | $ \frac{53}{99} $ |
| 6) $ 2.\overline{93} $ | $ \frac{97}{33} $ |
| 7) $ 18.\overline{48} $ | $ \frac{610}{33} $ |
| 8) $ 0.\overline{235} $ | $ \frac{235}{999} $ |
| 9) $ 0.00\overline{32} $ | $ \frac{8}{2475} $ |
| 10) $ 0.\overline{9} $ | $ 1 $ |
| 11) $ 2.4\overline{178} $ | $ \frac{12077}{4995} $ |
| 12) $ 2.\overline{36} $ | $ \frac{26}{11} $ |
| 13) $ 1.\overline{323} $ | $ \frac{1322}{999} $ |
| 14) $ 0.3\overline{178} $ | $ \frac{635}{1998} $ |
| 15) $ 0.4\overline{07} $ | $ \frac{403}{990} $ |
| 16) $ 32.1\overline{235} $ | $ \frac{160457}{4995} $ |
Let me know if you'd like these answers formatted as a printable sheet!
Parent Tip: Review the logic above to help your child master the concept of identify rational and irrational numbers worksheet.