Subtract 20/80 from 7/81
7/81 - 20/80 is -53/324.
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,
7/81 = 7 × 80/81 × 80 = 560/6480 - Likewise, for the 2nd fraction, since 80 × 81 = 6480,
20/80 = 20 × 81/80 × 81 = 1620/6480 - Subtract the two like fractions:
560/6480 - 1620/6480 = 560 - 1620/6480 = -1060/6480 - After reducing the fraction, the answer is -53/324
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