Subtract 42/63 from 8/21
8/21 - 42/63 is -2/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 63 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 21 × 3 = 63,
8/21 = 8 × 3/21 × 3 = 24/63 - Likewise, for the 2nd fraction, since 63 × 1 = 63,
42/63 = 42 × 1/63 × 1 = 42/63 - Subtract the two like fractions:
24/63 - 42/63 = 24 - 42/63 = -18/63 - After reducing the fraction, the answer is -2/7
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