Subtract 42/81 from 20/3, Solve 6 2/3

Subtract 42/81 from 20/3

1^st number: 6 2/3, 2^nd number: 42/81

20/3 - 42/81 is 166/27.

Find the least common denominator or LCM of the two denominators:
LCM of 3 and 81 is 81

Next, find the equivalent fraction of both fractional numbers with denominator 81
For the 1st fraction, since 3 × 27 = 81,
20/3 = 20 × 27/3 × 27 = 540/81
Likewise, for the 2nd fraction, since 81 × 1 = 81,
42/81 = 42 × 1/81 × 1 = 42/81
Subtract the two like fractions:
540/81 - 42/81 = 540 - 42/81 = 498/81
After reducing the fraction, the answer is 166/27
In mixed form: 64/27

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