Subtract 40/9 from 21/49, Solve 21/49

Subtract 40/9 from 21/49

1^st number: 21/49, 2^nd number: 4 4/9

21/49 - 40/9 is -253/63.

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,
40/9 = 40 × 49/9 × 49 = 1960/441
Subtract the two like fractions:
189/441 - 1960/441 = 189 - 1960/441 = -1771/441
After reducing the fraction, the answer is -253/63

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