Subtract 21/54 from 18/70
18/70 - 21/54 is -83/630.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 54 is 1890
Next, find the equivalent fraction of both fractional numbers with denominator 1890 - For the 1st fraction, since 70 × 27 = 1890,
18/70 = 18 × 27/70 × 27 = 486/1890 - Likewise, for the 2nd fraction, since 54 × 35 = 1890,
21/54 = 21 × 35/54 × 35 = 735/1890 - Subtract the two like fractions:
486/1890 - 735/1890 = 486 - 735/1890 = -249/1890 - After reducing the fraction, the answer is -83/630
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