Subtract 90/12 from 54/45, Solve 1 9/45

Subtract 90/12 from 54/45

1^st number: 1 9/45, 2^nd number: 7 6/12

54/45 - 90/12 is -63/10.

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,
54/45 = 54 × 4/45 × 4 = 216/180
Likewise, for the 2nd fraction, since 12 × 15 = 180,
90/12 = 90 × 15/12 × 15 = 1350/180
Subtract the two like fractions:
216/180 - 1350/180 = 216 - 1350/180 = -1134/180
After reducing the fraction, the answer is -63/10

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