Subtract 7/15 from 21/84
21/84 - 7/15 is -13/60.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 15 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420 - Likewise, for the 2nd fraction, since 15 × 28 = 420,
7/15 = 7 × 28/15 × 28 = 196/420 - Subtract the two like fractions:
105/420 - 196/420 = 105 - 196/420 = -91/420 - After reducing the fraction, the answer is -13/60
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