Subtract 81/5 from 8/42, Solve 8/42

Subtract 81/5 from 8/42

1^st number: 8/42, 2^nd number: 16 1/5

8/42 - 81/5 is -1681/105.

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,
8/42 = 8 × 5/42 × 5 = 40/210
Likewise, for the 2nd fraction, since 5 × 42 = 210,
81/5 = 81 × 42/5 × 42 = 3402/210
Subtract the two like fractions:
40/210 - 3402/210 = 40 - 3402/210 = -3362/210
After reducing the fraction, the answer is -1681/105

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