Subtract 45/54 from 21/49
21/49 - 45/54 is -17/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 49 and 54 is 2646
Next, find the equivalent fraction of both fractional numbers with denominator 2646 - For the 1st fraction, since 49 × 54 = 2646,
21/49 = 21 × 54/49 × 54 = 1134/2646 - Likewise, for the 2nd fraction, since 54 × 49 = 2646,
45/54 = 45 × 49/54 × 49 = 2205/2646 - Subtract the two like fractions:
1134/2646 - 2205/2646 = 1134 - 2205/2646 = -1071/2646 - After reducing the fraction, the answer is -17/42
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