Subtract 42/12 from 7/90, Solve 7/90

Subtract 42/12 from 7/90

1^st number: 7/90, 2^nd number: 3 6/12

7/90 - 42/12 is -154/45.

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,
7/90 = 7 × 2/90 × 2 = 14/180
Likewise, for the 2nd fraction, since 12 × 15 = 180,
42/12 = 42 × 15/12 × 15 = 630/180
Subtract the two like fractions:
14/180 - 630/180 = 14 - 630/180 = -616/180
After reducing the fraction, the answer is -154/45

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