Subtract 42/25 from 20/12, Solve 1 8/12

Subtract 42/25 from 20/12

1^st number: 1 8/12, 2^nd number: 1 17/25

20/12 - 42/25 is -1/75.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 25 is 300

Next, find the equivalent fraction of both fractional numbers with denominator 300
For the 1st fraction, since 12 × 25 = 300,
20/12 = 20 × 25/12 × 25 = 500/300
Likewise, for the 2nd fraction, since 25 × 12 = 300,
42/25 = 42 × 12/25 × 12 = 504/300
Subtract the two like fractions:
500/300 - 504/300 = 500 - 504/300 = -4/300
After reducing the fraction, the answer is -1/75

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