Subtract 1/80 from 21/81
21/81 - 1/80 is 533/2160.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 80 is 6480
Next, find the equivalent fraction of both fractional numbers with denominator 6480 - For the 1st fraction, since 81 × 80 = 6480,
21/81 = 21 × 80/81 × 80 = 1680/6480 - Likewise, for the 2nd fraction, since 80 × 81 = 6480,
1/80 = 1 × 81/80 × 81 = 81/6480 - Subtract the two like fractions:
1680/6480 - 81/6480 = 1680 - 81/6480 = 1599/6480 - After reducing the fraction, the answer is 533/2160
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