Subtract 15/27 from 21/70
21/70 - 15/27 is -23/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 27 is 1890
Next, find the equivalent fraction of both fractional numbers with denominator 1890 - For the 1st fraction, since 70 × 27 = 1890,
21/70 = 21 × 27/70 × 27 = 567/1890 - Likewise, for the 2nd fraction, since 27 × 70 = 1890,
15/27 = 15 × 70/27 × 70 = 1050/1890 - Subtract the two like fractions:
567/1890 - 1050/1890 = 567 - 1050/1890 = -483/1890 - After reducing the fraction, the answer is -23/90
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