Subtract 63/49 from 21/27, Solve 21/27

Subtract 63/49 from 21/27

1^st number: 21/27, 2^nd number: 1 14/49

21/27 - 63/49 is -32/63.

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

Next, find the equivalent fraction of both fractional numbers with denominator 1323
For the 1st fraction, since 27 × 49 = 1323,
21/27 = 21 × 49/27 × 49 = 1029/1323
Likewise, for the 2nd fraction, since 49 × 27 = 1323,
63/49 = 63 × 27/49 × 27 = 1701/1323
Subtract the two like fractions:
1029/1323 - 1701/1323 = 1029 - 1701/1323 = -672/1323
After reducing the fraction, the answer is -32/63

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