Subtract 30/9 from 21/49, Solve 21/49

Subtract 30/9 from 21/49

1^st number: 21/49, 2^nd number: 3 3/9

21/49 - 30/9 is -61/21.

Find the least common denominator or LCM of the two denominators:
LCM of 49 and 9 is 441

Next, find the equivalent fraction of both fractional numbers with denominator 441
For the 1st fraction, since 49 × 9 = 441,
21/49 = 21 × 9/49 × 9 = 189/441
Likewise, for the 2nd fraction, since 9 × 49 = 441,
30/9 = 30 × 49/9 × 49 = 1470/441
Subtract the two like fractions:
189/441 - 1470/441 = 189 - 1470/441 = -1281/441
After reducing the fraction, the answer is -61/21

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