Subtract 49/45 from 30/42, Solve 30/42

Subtract 49/45 from 30/42

1^st number: 30/42, 2^nd number: 1 4/45

30/42 - 49/45 is -118/315.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 45 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 42 × 15 = 630,
30/42 = 30 × 15/42 × 15 = 450/630
Likewise, for the 2nd fraction, since 45 × 14 = 630,
49/45 = 49 × 14/45 × 14 = 686/630
Subtract the two like fractions:
450/630 - 686/630 = 450 - 686/630 = -236/630
After reducing the fraction, the answer is -118/315

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