Subtract 21/12 from 30/84
1st number: 30/84, 2nd number: 1 9/12
30/84 - 21/12 is -39/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 12 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 84 × 1 = 84,
30/84 = 30 × 1/84 × 1 = 30/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
21/12 = 21 × 7/12 × 7 = 147/84 - Subtract the two like fractions:
30/84 - 147/84 = 30 - 147/84 = -117/84 - After reducing the fraction, the answer is -39/28
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