Subtract 21/9 from 30/84
1st number: 30/84, 2nd number: 2 3/9
30/84 - 21/9 is -83/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 9 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 84 × 3 = 252,
30/84 = 30 × 3/84 × 3 = 90/252 - Likewise, for the 2nd fraction, since 9 × 28 = 252,
21/9 = 21 × 28/9 × 28 = 588/252 - Subtract the two like fractions:
90/252 - 588/252 = 90 - 588/252 = -498/252 - After reducing the fraction, the answer is -83/42
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