Subtract 3/30 from 42/15, Solve 2 12/15

Subtract 3/30 from 42/15

1^st number: 2 12/15, 2^nd number: 3/30

42/15 - 3/30 is 27/10.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 30 is 30

Next, find the equivalent fraction of both fractional numbers with denominator 30
For the 1st fraction, since 15 × 2 = 30,
42/15 = 42 × 2/15 × 2 = 84/30
Likewise, for the 2nd fraction, since 30 × 1 = 30,
3/30 = 3 × 1/30 × 1 = 3/30
Subtract the two like fractions:
84/30 - 3/30 = 84 - 3/30 = 81/30
After reducing the fraction, the answer is 27/10
In mixed form: 27/10

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