Subtract 56/42 from 30/45, Solve 30/45

Subtract 56/42 from 30/45

1^st number: 30/45, 2^nd number: 1 14/42

30/45 - 56/42 is -2/3.

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

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 45 × 14 = 630,
30/45 = 30 × 14/45 × 14 = 420/630
Likewise, for the 2nd fraction, since 42 × 15 = 630,
56/42 = 56 × 15/42 × 15 = 840/630
Subtract the two like fractions:
420/630 - 840/630 = 420 - 840/630 = -420/630
After reducing the fraction, the answer is -2/3

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