Subtract 3/49 from 42/21, Solve 2 0/21

Subtract 3/49 from 42/21

1^st number: 2 0/21, 2^nd number: 3/49

42/21 - 3/49 is 95/49.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 49 is 147

Next, find the equivalent fraction of both fractional numbers with denominator 147
For the 1st fraction, since 21 × 7 = 147,
42/21 = 42 × 7/21 × 7 = 294/147
Likewise, for the 2nd fraction, since 49 × 3 = 147,
3/49 = 3 × 3/49 × 3 = 9/147
Subtract the two like fractions:
294/147 - 9/147 = 294 - 9/147 = 285/147
After reducing the fraction, the answer is 95/49
In mixed form: 146/49

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