Subtract 90/63 from 42/90, Solve 42/90

Subtract 90/63 from 42/90

1^st number: 42/90, 2^nd number: 1 27/63

42/90 - 90/63 is -101/105.

Find the least common denominator or LCM of the two denominators:
LCM of 90 and 63 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 90 × 7 = 630,
42/90 = 42 × 7/90 × 7 = 294/630
Likewise, for the 2nd fraction, since 63 × 10 = 630,
90/63 = 90 × 10/63 × 10 = 900/630
Subtract the two like fractions:
294/630 - 900/630 = 294 - 900/630 = -606/630
After reducing the fraction, the answer is -101/105

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