Subtract 90/45 from 5/42, Solve 5/42

Subtract 90/45 from 5/42

1^st number: 5/42, 2^nd number: 2 0/45

5/42 - 90/45 is -79/42.

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,
5/42 = 5 × 15/42 × 15 = 75/630
Likewise, for the 2nd fraction, since 45 × 14 = 630,
90/45 = 90 × 14/45 × 14 = 1260/630
Subtract the two like fractions:
75/630 - 1260/630 = 75 - 1260/630 = -1185/630
After reducing the fraction, the answer is -79/42

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