Subtract 18/7 from 42/63
1st number: 42/63, 2nd number: 2 4/7
42/63 - 18/7 is -40/21.
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,
42/63 = 42 × 1/63 × 1 = 42/63 - Likewise, for the 2nd fraction, since 7 × 9 = 63,
18/7 = 18 × 9/7 × 9 = 162/63 - Subtract the two like fractions:
42/63 - 162/63 = 42 - 162/63 = -120/63 - After reducing the fraction, the answer is -40/21
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