Subtract 30/18 from 20/28
1st number: 20/28, 2nd number: 1 12/18
20/28 - 30/18 is -20/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 18 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 28 × 9 = 252,
20/28 = 20 × 9/28 × 9 = 180/252 - Likewise, for the 2nd fraction, since 18 × 14 = 252,
30/18 = 30 × 14/18 × 14 = 420/252 - Subtract the two like fractions:
180/252 - 420/252 = 180 - 420/252 = -240/252 - After reducing the fraction, the answer is -20/21
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