Subtract 15/7 from 21/54
1st number: 21/54, 2nd number: 2 1/7
21/54 - 15/7 is -221/126.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 7 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 54 × 7 = 378,
21/54 = 21 × 7/54 × 7 = 147/378 - Likewise, for the 2nd fraction, since 7 × 54 = 378,
15/7 = 15 × 54/7 × 54 = 810/378 - Subtract the two like fractions:
147/378 - 810/378 = 147 - 810/378 = -663/378 - After reducing the fraction, the answer is -221/126
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