Subtract 20/8 from 2/42, Solve 2/42

Subtract 20/8 from 2/42

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

2/42 - 20/8 is -103/42.

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,
2/42 = 2 × 4/42 × 4 = 8/168
Likewise, for the 2nd fraction, since 8 × 21 = 168,
20/8 = 20 × 21/8 × 21 = 420/168
Subtract the two like fractions:
8/168 - 420/168 = 8 - 420/168 = -412/168
After reducing the fraction, the answer is -103/42

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