Subtract 40/18 from 21/49, Solve 21/49

Subtract 40/18 from 21/49

1^st number: 21/49, 2^nd number: 2 4/18

21/49 - 40/18 is -113/63.

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,
21/49 = 21 × 18/49 × 18 = 378/882
Likewise, for the 2nd fraction, since 18 × 49 = 882,
40/18 = 40 × 49/18 × 49 = 1960/882
Subtract the two like fractions:
378/882 - 1960/882 = 378 - 1960/882 = -1582/882
After reducing the fraction, the answer is -113/63

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