Subtract 21/36 from 30/18, Solve 1 12/18

Subtract 21/36 from 30/18

1^st number: 1 12/18, 2^nd number: 21/36

30/18 - 21/36 is 13/12.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 36 is 36

Next, find the equivalent fraction of both fractional numbers with denominator 36
For the 1st fraction, since 18 × 2 = 36,
30/18 = 30 × 2/18 × 2 = 60/36
Likewise, for the 2nd fraction, since 36 × 1 = 36,
21/36 = 21 × 1/36 × 1 = 21/36
Subtract the two like fractions:
60/36 - 21/36 = 60 - 21/36 = 39/36
After reducing the fraction, the answer is 13/12
In mixed form: 11/12

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