Subtract 9/5 from 54/42, Solve 1 12/42

Subtract 9/5 from 54/42

1^st number: 1 12/42, 2^nd number: 1 4/5

54/42 - 9/5 is -18/35.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 5 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 42 × 5 = 210,
54/42 = 54 × 5/42 × 5 = 270/210
Likewise, for the 2nd fraction, since 5 × 42 = 210,
9/5 = 9 × 42/5 × 42 = 378/210
Subtract the two like fractions:
270/210 - 378/210 = 270 - 378/210 = -108/210
After reducing the fraction, the answer is -18/35

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