Subtract 28/30 from 21/54
21/54 - 28/30 is -49/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 30 is 270
Next, find the equivalent fraction of both fractional numbers with denominator 270 - For the 1st fraction, since 54 × 5 = 270,
21/54 = 21 × 5/54 × 5 = 105/270 - Likewise, for the 2nd fraction, since 30 × 9 = 270,
28/30 = 28 × 9/30 × 9 = 252/270 - Subtract the two like fractions:
105/270 - 252/270 = 105 - 252/270 = -147/270 - After reducing the fraction, the answer is -49/90
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