Subtract 15/4 from 15/21
1st number: 15/21, 2nd number: 3 3/4
15/21 - 15/4 is -85/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 4 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
15/21 = 15 × 4/21 × 4 = 60/84 - Likewise, for the 2nd fraction, since 4 × 21 = 84,
15/4 = 15 × 21/4 × 21 = 315/84 - Subtract the two like fractions:
60/84 - 315/84 = 60 - 315/84 = -255/84 - After reducing the fraction, the answer is -85/28
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