Subtract 63/45 from 30/42, Solve 30/42

Subtract 63/45 from 30/42

1^st number: 30/42, 2^nd number: 1 18/45

30/42 - 63/45 is -24/35.

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,
63/45 = 63 × 14/45 × 14 = 882/630
Subtract the two like fractions:
450/630 - 882/630 = 450 - 882/630 = -432/630
After reducing the fraction, the answer is -24/35

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