Subtract 6/8 from 27/21, Solve 1 6/21

Subtract 6/8 from 27/21

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

27/21 - 6/8 is 15/28.

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

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 21 × 8 = 168,
27/21 = 27 × 8/21 × 8 = 216/168
Likewise, for the 2nd fraction, since 8 × 21 = 168,
6/8 = 6 × 21/8 × 21 = 126/168
Subtract the two like fractions:
216/168 - 126/168 = 216 - 126/168 = 90/168
After reducing the fraction, the answer is 15/28

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