Subtract 9/90 from 45/12, Solve 3 9/12

Subtract 9/90 from 45/12

1^st number: 3 9/12, 2^nd number: 9/90

45/12 - 9/90 is 73/20.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 90 is 180

Next, find the equivalent fraction of both fractional numbers with denominator 180
For the 1st fraction, since 12 × 15 = 180,
45/12 = 45 × 15/12 × 15 = 675/180
Likewise, for the 2nd fraction, since 90 × 2 = 180,
9/90 = 9 × 2/90 × 2 = 18/180
Subtract the two like fractions:
675/180 - 18/180 = 675 - 18/180 = 657/180
After reducing the fraction, the answer is 73/20
In mixed form: 313/20

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