Subtract 21/81 from 16/5, Solve 3 1/5

Subtract 21/81 from 16/5

1^st number: 3 1/5, 2^nd number: 21/81

16/5 - 21/81 is 397/135.

Find the least common denominator or LCM of the two denominators:
LCM of 5 and 81 is 405

Next, find the equivalent fraction of both fractional numbers with denominator 405
For the 1st fraction, since 5 × 81 = 405,
16/5 = 16 × 81/5 × 81 = 1296/405
Likewise, for the 2nd fraction, since 81 × 5 = 405,
21/81 = 21 × 5/81 × 5 = 105/405
Subtract the two like fractions:
1296/405 - 105/405 = 1296 - 105/405 = 1191/405
After reducing the fraction, the answer is 397/135
In mixed form: 2127/135

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