Subtract 20/8 from 60/42, Solve 1 18/42

Subtract 20/8 from 60/42

1^st number: 1 18/42, 2^nd number: 2 4/8

60/42 - 20/8 is -15/14.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 8 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 42 × 4 = 168,
60/42 = 60 × 4/42 × 4 = 240/168
Likewise, for the 2nd fraction, since 8 × 21 = 168,
20/8 = 20 × 21/8 × 21 = 420/168
Subtract the two like fractions:
240/168 - 420/168 = 240 - 420/168 = -180/168
After reducing the fraction, the answer is -15/14

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