Subtract 21/90 from 12/54
12/54 - 21/90 is -1/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 90 is 270
Next, find the equivalent fraction of both fractional numbers with denominator 270 - For the 1st fraction, since 54 × 5 = 270,
12/54 = 12 × 5/54 × 5 = 60/270 - Likewise, for the 2nd fraction, since 90 × 3 = 270,
21/90 = 21 × 3/90 × 3 = 63/270 - Subtract the two like fractions:
60/270 - 63/270 = 60 - 63/270 = -3/270 - After reducing the fraction, the answer is -1/90
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