Subtract 70/81 from 4/80
4/80 - 70/81 is -1319/1620.
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,
4/80 = 4 × 81/80 × 81 = 324/6480 - Likewise, for the 2nd fraction, since 81 × 80 = 6480,
70/81 = 70 × 80/81 × 80 = 5600/6480 - Subtract the two like fractions:
324/6480 - 5600/6480 = 324 - 5600/6480 = -5276/6480 - After reducing the fraction, the answer is -1319/1620
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