Subtract 3/81 from 40/7, Solve 5 5/7

Subtract 3/81 from 40/7

1^st number: 5 5/7, 2^nd number: 3/81

40/7 - 3/81 is 1073/189.

Find the least common denominator or LCM of the two denominators:
LCM of 7 and 81 is 567

Next, find the equivalent fraction of both fractional numbers with denominator 567
For the 1st fraction, since 7 × 81 = 567,
40/7 = 40 × 81/7 × 81 = 3240/567
Likewise, for the 2nd fraction, since 81 × 7 = 567,
3/81 = 3 × 7/81 × 7 = 21/567
Subtract the two like fractions:
3240/567 - 21/567 = 3240 - 21/567 = 3219/567
After reducing the fraction, the answer is 1073/189
In mixed form: 5128/189

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