Subtract 9/12 from 81/45, Solve 1 36/45

Subtract 9/12 from 81/45

1^st number: 1 36/45, 2^nd number: 9/12

81/45 - 9/12 is 21/20.

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,
81/45 = 81 × 4/45 × 4 = 324/180
Likewise, for the 2nd fraction, since 12 × 15 = 180,
9/12 = 9 × 15/12 × 15 = 135/180
Subtract the two like fractions:
324/180 - 135/180 = 324 - 135/180 = 189/180
After reducing the fraction, the answer is 21/20
In mixed form: 11/20

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