Subtract 20/12 from 10/90, Solve 10/90

Subtract 20/12 from 10/90

1^st number: 10/90, 2^nd number: 1 8/12

10/90 - 20/12 is -14/9.

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,
10/90 = 10 × 2/90 × 2 = 20/180
Likewise, for the 2nd fraction, since 12 × 15 = 180,
20/12 = 20 × 15/12 × 15 = 300/180
Subtract the two like fractions:
20/180 - 300/180 = 20 - 300/180 = -280/180
After reducing the fraction, the answer is -14/9

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