Subtract 80/49 from 30/21, Solve 1 9/21

Subtract 80/49 from 30/21

1^st number: 1 9/21, 2^nd number: 1 31/49

30/21 - 80/49 is -10/49.

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,
30/21 = 30 × 7/21 × 7 = 210/147
Likewise, for the 2nd fraction, since 49 × 3 = 147,
80/49 = 80 × 3/49 × 3 = 240/147
Subtract the two like fractions:
210/147 - 240/147 = 210 - 240/147 = -30/147
After reducing the fraction, the answer is -10/49

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