Subtract 90/12 from 30/45, Solve 30/45

Subtract 90/12 from 30/45

1^st number: 30/45, 2^nd number: 7 6/12

30/45 - 90/12 is -41/6.

Find the least common denominator or LCM of the two denominators:
LCM of 45 and 12 is 180

Next, find the equivalent fraction of both fractional numbers with denominator 180
For the 1st fraction, since 45 × 4 = 180,
30/45 = 30 × 4/45 × 4 = 120/180
Likewise, for the 2nd fraction, since 12 × 15 = 180,
90/12 = 90 × 15/12 × 15 = 1350/180
Subtract the two like fractions:
120/180 - 1350/180 = 120 - 1350/180 = -1230/180
After reducing the fraction, the answer is -41/6

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