Subtract 30/21 from 20/36
1st number: 20/36, 2nd number: 1 9/21
20/36 - 30/21 is -55/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 21 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 36 × 7 = 252,
20/36 = 20 × 7/36 × 7 = 140/252 - Likewise, for the 2nd fraction, since 21 × 12 = 252,
30/21 = 30 × 12/21 × 12 = 360/252 - Subtract the two like fractions:
140/252 - 360/252 = 140 - 360/252 = -220/252 - After reducing the fraction, the answer is -55/63
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