Subtract 30/21 from 20/18
1st number: 1 2/18, 2nd number: 1 9/21
20/18 - 30/21 is -20/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 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 21 × 6 = 126,
30/21 = 30 × 6/21 × 6 = 180/126 - Subtract the two like fractions:
140/126 - 180/126 = 140 - 180/126 = -40/126 - After reducing the fraction, the answer is -20/63
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