Subtract 21/54 from 2/7
2/7 - 21/54 is -13/126.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 54 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 7 × 54 = 378,
2/7 = 2 × 54/7 × 54 = 108/378 - Likewise, for the 2nd fraction, since 54 × 7 = 378,
21/54 = 21 × 7/54 × 7 = 147/378 - Subtract the two like fractions:
108/378 - 147/378 = 108 - 147/378 = -39/378 - After reducing the fraction, the answer is -13/126
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