Subtract 20/42 from 21/12
1st number: 1 9/12, 2nd number: 20/42
21/12 - 20/42 is 107/84.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 42 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
21/12 = 21 × 7/12 × 7 = 147/84 - Likewise, for the 2nd fraction, since 42 × 2 = 84,
20/42 = 20 × 2/42 × 2 = 40/84 - Subtract the two like fractions:
147/84 - 40/84 = 147 - 40/84 = 107/84 - In mixed form: 123/84
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