Subtract 84/18 from 21/49, Solve 21/49

Subtract 84/18 from 21/49

1^st number: 21/49, 2^nd number: 4 12/18

21/49 - 84/18 is -89/21.

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,
84/18 = 84 × 49/18 × 49 = 4116/882
Subtract the two like fractions:
378/882 - 4116/882 = 378 - 4116/882 = -3738/882
After reducing the fraction, the answer is -89/21

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