Subtract 21/42 from 12/8, Solve 1 4/8

Subtract 21/42 from 12/8

1^st number: 1 4/8, 2^nd number: 21/42

12/8 - 21/42 is 1/1.

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

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 8 × 21 = 168,
12/8 = 12 × 21/8 × 21 = 252/168
Likewise, for the 2nd fraction, since 42 × 4 = 168,
21/42 = 21 × 4/42 × 4 = 84/168
Subtract the two like fractions:
252/168 - 84/168 = 252 - 84/168 = 168/168
After reducing the fraction, the answer is 1/1

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