Subtract 7/12 from 30/90, Solve 30/90

Subtract 7/12 from 30/90

30/90 - 7/12 is -1/4.

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,
30/90 = 30 × 2/90 × 2 = 60/180
Likewise, for the 2nd fraction, since 12 × 15 = 180,
7/12 = 7 × 15/12 × 15 = 105/180
Subtract the two like fractions:
60/180 - 105/180 = 60 - 105/180 = -45/180
After reducing the fraction, the answer is -1/4

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