Subtract 42/12 from 30/50, Solve 30/50

Subtract 42/12 from 30/50

1^st number: 30/50, 2^nd number: 3 6/12

30/50 - 42/12 is -29/10.

Find the least common denominator or LCM of the two denominators:
LCM of 50 and 12 is 300

Next, find the equivalent fraction of both fractional numbers with denominator 300
For the 1st fraction, since 50 × 6 = 300,
30/50 = 30 × 6/50 × 6 = 180/300
Likewise, for the 2nd fraction, since 12 × 25 = 300,
42/12 = 42 × 25/12 × 25 = 1050/300
Subtract the two like fractions:
180/300 - 1050/300 = 180 - 1050/300 = -870/300
After reducing the fraction, the answer is -29/10

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