Subtract 27/28 from 42/30, Solve 1 12/30

Subtract 27/28 from 42/30

1^st number: 1 12/30, 2^nd number: 27/28

42/30 - 27/28 is 61/140.

Find the least common denominator or LCM of the two denominators:
LCM of 30 and 28 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 30 × 14 = 420,
42/30 = 42 × 14/30 × 14 = 588/420
Likewise, for the 2nd fraction, since 28 × 15 = 420,
27/28 = 27 × 15/28 × 15 = 405/420
Subtract the two like fractions:
588/420 - 405/420 = 588 - 405/420 = 183/420
After reducing the fraction, the answer is 61/140

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