Subtract 10/30 from 42/12, Solve 3 6/12

Subtract 10/30 from 42/12

1^st number: 3 6/12, 2^nd number: 10/30

42/12 - 10/30 is 19/6.

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,
10/30 = 10 × 2/30 × 2 = 20/60
Subtract the two like fractions:
210/60 - 20/60 = 210 - 20/60 = 190/60
After reducing the fraction, the answer is 19/6
In mixed form: 31/6

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