Subtract 21/42 from 20/18
1st number: 1 2/18, 2nd number: 21/42
20/18 - 21/42 is 11/18.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 42 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
20/18 = 20 × 7/18 × 7 = 140/126 - Likewise, for the 2nd fraction, since 42 × 3 = 126,
21/42 = 21 × 3/42 × 3 = 63/126 - Subtract the two like fractions:
140/126 - 63/126 = 140 - 63/126 = 77/126 - After reducing the fraction, the answer is 11/18
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