Subtract 15/21 from 21/63
21/63 - 15/21 is -8/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 21 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 63 × 1 = 63,
21/63 = 21 × 1/63 × 1 = 21/63 - Likewise, for the 2nd fraction, since 21 × 3 = 63,
15/21 = 15 × 3/21 × 3 = 45/63 - Subtract the two like fractions:
21/63 - 45/63 = 21 - 45/63 = -24/63 - After reducing the fraction, the answer is -8/21
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