Subtract 42/12 from 5/90, Solve 5/90

Subtract 42/12 from 5/90

1^st number: 5/90, 2^nd number: 3 6/12

5/90 - 42/12 is -31/9.

Find the least common denominator or LCM of the two denominators:
LCM of 90 and 12 is 180

Next, find the equivalent fraction of both fractional numbers with denominator 180
For the 1st fraction, since 90 × 2 = 180,
5/90 = 5 × 2/90 × 2 = 10/180
Likewise, for the 2nd fraction, since 12 × 15 = 180,
42/12 = 42 × 15/12 × 15 = 630/180
Subtract the two like fractions:
10/180 - 630/180 = 10 - 630/180 = -620/180
After reducing the fraction, the answer is -31/9

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