Subtract 15/27 from 21/90
21/90 - 15/27 is -29/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 27 is 270
Next, find the equivalent fraction of both fractional numbers with denominator 270 - For the 1st fraction, since 90 × 3 = 270,
21/90 = 21 × 3/90 × 3 = 63/270 - Likewise, for the 2nd fraction, since 27 × 10 = 270,
15/27 = 15 × 10/27 × 10 = 150/270 - Subtract the two like fractions:
63/270 - 150/270 = 63 - 150/270 = -87/270 - After reducing the fraction, the answer is -29/90
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