Subtract 72/84 from 90/8, Solve 11 2/8

Subtract 72/84 from 90/8

1^st number: 11 2/8, 2^nd number: 72/84

90/8 - 72/84 is 291/28.

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,
90/8 = 90 × 21/8 × 21 = 1890/168
Likewise, for the 2nd fraction, since 84 × 2 = 168,
72/84 = 72 × 2/84 × 2 = 144/168
Subtract the two like fractions:
1890/168 - 144/168 = 1890 - 144/168 = 1746/168
After reducing the fraction, the answer is 291/28
In mixed form: 1011/28

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