Subtract 84/27 from 21/49, Solve 21/49

Subtract 84/27 from 21/49

1^st number: 21/49, 2^nd number: 3 3/27

21/49 - 84/27 is -169/63.

Find the least common denominator or LCM of the two denominators:
LCM of 49 and 27 is 1323

Next, find the equivalent fraction of both fractional numbers with denominator 1323
For the 1st fraction, since 49 × 27 = 1323,
21/49 = 21 × 27/49 × 27 = 567/1323
Likewise, for the 2nd fraction, since 27 × 49 = 1323,
84/27 = 84 × 49/27 × 49 = 4116/1323
Subtract the two like fractions:
567/1323 - 4116/1323 = 567 - 4116/1323 = -3549/1323
After reducing the fraction, the answer is -169/63

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