Subtract 21/81 from 54/21, Solve 2 12/21

Subtract 21/81 from 54/21

1^st number: 2 12/21, 2^nd number: 21/81

54/21 - 21/81 is 437/189.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 81 is 567

Next, find the equivalent fraction of both fractional numbers with denominator 567
For the 1st fraction, since 21 × 27 = 567,
54/21 = 54 × 27/21 × 27 = 1458/567
Likewise, for the 2nd fraction, since 81 × 7 = 567,
21/81 = 21 × 7/81 × 7 = 147/567
Subtract the two like fractions:
1458/567 - 147/567 = 1458 - 147/567 = 1311/567
After reducing the fraction, the answer is 437/189
In mixed form: 259/189

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