Subtract 30/8 from 1/84, Solve 1/84

Subtract 30/8 from 1/84

1^st number: 1/84, 2^nd number: 3 6/8

1/84 - 30/8 is -157/42.

Find the least common denominator or LCM of the two denominators:
LCM of 84 and 8 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 84 × 2 = 168,
1/84 = 1 × 2/84 × 2 = 2/168
Likewise, for the 2nd fraction, since 8 × 21 = 168,
30/8 = 30 × 21/8 × 21 = 630/168
Subtract the two like fractions:
2/168 - 630/168 = 2 - 630/168 = -628/168
After reducing the fraction, the answer is -157/42

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