Subtract 30/27 from 10/42, Solve 10/42

Subtract 30/27 from 10/42

1^st number: 10/42, 2^nd number: 1 3/27

10/42 - 30/27 is -55/63.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 27 is 378

Next, find the equivalent fraction of both fractional numbers with denominator 378
For the 1st fraction, since 42 × 9 = 378,
10/42 = 10 × 9/42 × 9 = 90/378
Likewise, for the 2nd fraction, since 27 × 14 = 378,
30/27 = 30 × 14/27 × 14 = 420/378
Subtract the two like fractions:
90/378 - 420/378 = 90 - 420/378 = -330/378
After reducing the fraction, the answer is -55/63

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