Subtract 70/49 from 20/18, Solve 1 2/18

Subtract 70/49 from 20/18

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

20/18 - 70/49 is -20/63.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 49 is 882

Next, find the equivalent fraction of both fractional numbers with denominator 882
For the 1st fraction, since 18 × 49 = 882,
20/18 = 20 × 49/18 × 49 = 980/882
Likewise, for the 2nd fraction, since 49 × 18 = 882,
70/49 = 70 × 18/49 × 18 = 1260/882
Subtract the two like fractions:
980/882 - 1260/882 = 980 - 1260/882 = -280/882
After reducing the fraction, the answer is -20/63

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