Subtract 90/84 from 30/8, Solve 3 6/8

Subtract 90/84 from 30/8

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

30/8 - 90/84 is 75/28.

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,
90/84 = 90 × 2/84 × 2 = 180/168
Subtract the two like fractions:
630/168 - 180/168 = 630 - 180/168 = 450/168
After reducing the fraction, the answer is 75/28
In mixed form: 219/28

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