Subtract 30/63 from 30/21
1st number: 1 9/21, 2nd number: 30/63
30/21 - 30/63 is 20/21.
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,
30/21 = 30 × 3/21 × 3 = 90/63 - Likewise, for the 2nd fraction, since 63 × 1 = 63,
30/63 = 30 × 1/63 × 1 = 30/63 - Subtract the two like fractions:
90/63 - 30/63 = 90 - 30/63 = 60/63 - After reducing the fraction, the answer is 20/21
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