Subtract 21/54 from 3/15
3/15 - 21/54 is -17/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 54 is 270
Next, find the equivalent fraction of both fractional numbers with denominator 270 - For the 1st fraction, since 15 × 18 = 270,
3/15 = 3 × 18/15 × 18 = 54/270 - Likewise, for the 2nd fraction, since 54 × 5 = 270,
21/54 = 21 × 5/54 × 5 = 105/270 - Subtract the two like fractions:
54/270 - 105/270 = 54 - 105/270 = -51/270 - After reducing the fraction, the answer is -17/90
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