Subtract 1/48 from 21/81, Solve 21/81

Subtract 1/48 from 21/81

21/81 - 1/48 is 103/432.

Find the least common denominator or LCM of the two denominators:
LCM of 81 and 48 is 1296

Next, find the equivalent fraction of both fractional numbers with denominator 1296
For the 1st fraction, since 81 × 16 = 1296,
21/81 = 21 × 16/81 × 16 = 336/1296
Likewise, for the 2nd fraction, since 48 × 27 = 1296,
1/48 = 1 × 27/48 × 27 = 27/1296
Subtract the two like fractions:
336/1296 - 27/1296 = 336 - 27/1296 = 309/1296
After reducing the fraction, the answer is 103/432

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