Subtract 45/70 from 21/54
21/54 - 45/70 is -16/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 70 is 1890
Next, find the equivalent fraction of both fractional numbers with denominator 1890 - For the 1st fraction, since 54 × 35 = 1890,
21/54 = 21 × 35/54 × 35 = 735/1890 - Likewise, for the 2nd fraction, since 70 × 27 = 1890,
45/70 = 45 × 27/70 × 27 = 1215/1890 - Subtract the two like fractions:
735/1890 - 1215/1890 = 735 - 1215/1890 = -480/1890 - After reducing the fraction, the answer is -16/63
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