Subtract 18/21 from 54/8, Solve 6 6/8

Subtract 18/21 from 54/8

1^st number: 6 6/8, 2^nd number: 18/21

54/8 - 18/21 is 165/28.

Find the least common denominator or LCM of the two denominators:
LCM of 8 and 21 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 8 × 21 = 168,
54/8 = 54 × 21/8 × 21 = 1134/168
Likewise, for the 2nd fraction, since 21 × 8 = 168,
18/21 = 18 × 8/21 × 8 = 144/168
Subtract the two like fractions:
1134/168 - 144/168 = 1134 - 144/168 = 990/168
After reducing the fraction, the answer is 165/28
In mixed form: 525/28

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