Subtract 20/81 from 6/90
6/90 - 20/81 is -73/405.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 81 is 810
Next, find the equivalent fraction of both fractional numbers with denominator 810 - For the 1st fraction, since 90 × 9 = 810,
6/90 = 6 × 9/90 × 9 = 54/810 - Likewise, for the 2nd fraction, since 81 × 10 = 810,
20/81 = 20 × 10/81 × 10 = 200/810 - Subtract the two like fractions:
54/810 - 200/810 = 54 - 200/810 = -146/810 - After reducing the fraction, the answer is -73/405
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