Subtract 40/63 from 8/21
8/21 - 40/63 is -16/63.
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,
40/63 = 40 × 1/63 × 1 = 40/63 - Subtract the two like fractions:
24/63 - 40/63 = 24 - 40/63 = -16/63
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