Subtract 18/63 from 20/21
20/21 - 18/63 is 2/3.
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,
20/21 = 20 × 3/21 × 3 = 60/63 - Likewise, for the 2nd fraction, since 63 × 1 = 63,
18/63 = 18 × 1/63 × 1 = 18/63 - Subtract the two like fractions:
60/63 - 18/63 = 60 - 18/63 = 42/63 - After reducing the fraction, the answer is 2/3
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