Subtract 20/18 from 42/49
1st number: 42/49, 2nd number: 1 2/18
42/49 - 20/18 is -16/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 49 and 18 is 882
Next, find the equivalent fraction of both fractional numbers with denominator 882 - For the 1st fraction, since 49 × 18 = 882,
42/49 = 42 × 18/49 × 18 = 756/882 - Likewise, for the 2nd fraction, since 18 × 49 = 882,
20/18 = 20 × 49/18 × 49 = 980/882 - Subtract the two like fractions:
756/882 - 980/882 = 756 - 980/882 = -224/882 - After reducing the fraction, the answer is -16/63
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