Subtract 5/84 from 30/8, Solve 3 6/8

Subtract 5/84 from 30/8

1^st number: 3 6/8, 2^nd number: 5/84

30/8 - 5/84 is 155/42.

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

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 8 × 21 = 168,
30/8 = 30 × 21/8 × 21 = 630/168
Likewise, for the 2nd fraction, since 84 × 2 = 168,
5/84 = 5 × 2/84 × 2 = 10/168
Subtract the two like fractions:
630/168 - 10/168 = 630 - 10/168 = 620/168
After reducing the fraction, the answer is 155/42
In mixed form: 329/42

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