Subtract 18/7 from 21/63
1st number: 21/63, 2nd number: 2 4/7
21/63 - 18/7 is -47/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 7 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 7 × 9 = 63,
18/7 = 18 × 9/7 × 9 = 162/63 - Subtract the two like fractions:
21/63 - 162/63 = 21 - 162/63 = -141/63 - After reducing the fraction, the answer is -47/21
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