Subtract 42/30 from 42/12, Solve 3 6/12

Subtract 42/30 from 42/12

1^st number: 3 6/12, 2^nd number: 1 12/30

42/12 - 42/30 is 21/10.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 30 is 60

Next, find the equivalent fraction of both fractional numbers with denominator 60
For the 1st fraction, since 12 × 5 = 60,
42/12 = 42 × 5/12 × 5 = 210/60
Likewise, for the 2nd fraction, since 30 × 2 = 60,
42/30 = 42 × 2/30 × 2 = 84/60
Subtract the two like fractions:
210/60 - 84/60 = 210 - 84/60 = 126/60
After reducing the fraction, the answer is 21/10
In mixed form: 21/10

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