Subtract 42/72 from 30/18, Solve 1 12/18

Subtract 42/72 from 30/18

1^st number: 1 12/18, 2^nd number: 42/72

30/18 - 42/72 is 13/12.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 72 is 72

Next, find the equivalent fraction of both fractional numbers with denominator 72
For the 1st fraction, since 18 × 4 = 72,
30/18 = 30 × 4/18 × 4 = 120/72
Likewise, for the 2nd fraction, since 72 × 1 = 72,
42/72 = 42 × 1/72 × 1 = 42/72
Subtract the two like fractions:
120/72 - 42/72 = 120 - 42/72 = 78/72
After reducing the fraction, the answer is 13/12
In mixed form: 11/12

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