Subtract 48/30 from 18/28, Solve 18/28

Subtract 48/30 from 18/28

1^st number: 18/28, 2^nd number: 1 18/30

18/28 - 48/30 is -67/70.

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

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 28 × 15 = 420,
18/28 = 18 × 15/28 × 15 = 270/420
Likewise, for the 2nd fraction, since 30 × 14 = 420,
48/30 = 48 × 14/30 × 14 = 672/420
Subtract the two like fractions:
270/420 - 672/420 = 270 - 672/420 = -402/420
After reducing the fraction, the answer is -67/70

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