Subtract 20/21 from 18/6, Solve 3 0/6

Subtract 20/21 from 18/6

1^st number: 3 0/6, 2^nd number: 20/21

18/6 - 20/21 is 43/21.

Find the least common denominator or LCM of the two denominators:
LCM of 6 and 21 is 42

Next, find the equivalent fraction of both fractional numbers with denominator 42
For the 1st fraction, since 6 × 7 = 42,
18/6 = 18 × 7/6 × 7 = 126/42
Likewise, for the 2nd fraction, since 21 × 2 = 42,
20/21 = 20 × 2/21 × 2 = 40/42
Subtract the two like fractions:
126/42 - 40/42 = 126 - 40/42 = 86/42
After reducing the fraction, the answer is 43/21
In mixed form: 21/21

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