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

Subtract 21/18 from 40/49

1^st number: 40/49, 2^nd number: 1 3/18

40/49 - 21/18 is -103/294.

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,
40/49 = 40 × 18/49 × 18 = 720/882
Likewise, for the 2nd fraction, since 18 × 49 = 882,
21/18 = 21 × 49/18 × 49 = 1029/882
Subtract the two like fractions:
720/882 - 1029/882 = 720 - 1029/882 = -309/882
After reducing the fraction, the answer is -103/294

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