Subtract 2/81 from 4/8, Solve 4/8

Subtract 2/81 from 4/8

4/8 - 2/81 is 77/162.

Find the least common denominator or LCM of the two denominators:
LCM of 8 and 81 is 648

Next, find the equivalent fraction of both fractional numbers with denominator 648
For the 1st fraction, since 8 × 81 = 648,
4/8 = 4 × 81/8 × 81 = 324/648
Likewise, for the 2nd fraction, since 81 × 8 = 648,
2/81 = 2 × 8/81 × 8 = 16/648
Subtract the two like fractions:
324/648 - 16/648 = 324 - 16/648 = 308/648
After reducing the fraction, the answer is 77/162

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