Subtract 21/54 from 20/90
20/90 - 21/54 is -1/6.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 54 is 270
Next, find the equivalent fraction of both fractional numbers with denominator 270 - For the 1st fraction, since 90 × 3 = 270,
20/90 = 20 × 3/90 × 3 = 60/270 - Likewise, for the 2nd fraction, since 54 × 5 = 270,
21/54 = 21 × 5/54 × 5 = 105/270 - Subtract the two like fractions:
60/270 - 105/270 = 60 - 105/270 = -45/270 - After reducing the fraction, the answer is -1/6
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