Subtract 28/24 from 3/42, Solve 3/42

Subtract 28/24 from 3/42

1^st number: 3/42, 2^nd number: 1 4/24

3/42 - 28/24 is -23/21.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 24 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 42 × 4 = 168,
3/42 = 3 × 4/42 × 4 = 12/168
Likewise, for the 2nd fraction, since 24 × 7 = 168,
28/24 = 28 × 7/24 × 7 = 196/168
Subtract the two like fractions:
12/168 - 196/168 = 12 - 196/168 = -184/168
After reducing the fraction, the answer is -23/21

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