Subtract 2/8 from 20/21, Solve 20/21

Subtract 2/8 from 20/21

20/21 - 2/8 is 59/84.

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,
20/21 = 20 × 8/21 × 8 = 160/168
Likewise, for the 2nd fraction, since 8 × 21 = 168,
2/8 = 2 × 21/8 × 21 = 42/168
Subtract the two like fractions:
160/168 - 42/168 = 160 - 42/168 = 118/168
After reducing the fraction, the answer is 59/84

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