Subtract 25/81 from 21/80
21/80 - 25/81 is -299/6480.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 81 is 6480
Next, find the equivalent fraction of both fractional numbers with denominator 6480 - For the 1st fraction, since 80 × 81 = 6480,
21/80 = 21 × 81/80 × 81 = 1701/6480 - Likewise, for the 2nd fraction, since 81 × 80 = 6480,
25/81 = 25 × 80/81 × 80 = 2000/6480 - Subtract the two like fractions:
1701/6480 - 2000/6480 = 1701 - 2000/6480 = -299/6480
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