Subtract 80/49 from 30/42, Solve 30/42

Subtract 80/49 from 30/42

1^st number: 30/42, 2^nd number: 1 31/49

30/42 - 80/49 is -45/49.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 49 is 294

Next, find the equivalent fraction of both fractional numbers with denominator 294
For the 1st fraction, since 42 × 7 = 294,
30/42 = 30 × 7/42 × 7 = 210/294
Likewise, for the 2nd fraction, since 49 × 6 = 294,
80/49 = 80 × 6/49 × 6 = 480/294
Subtract the two like fractions:
210/294 - 480/294 = 210 - 480/294 = -270/294
After reducing the fraction, the answer is -45/49

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