Subtract 54/18 from 45/21
1st number: 2 3/21, 2nd number: 3 0/18
45/21 - 54/18 is -6/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 21 × 6 = 126,
45/21 = 45 × 6/21 × 6 = 270/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
54/18 = 54 × 7/18 × 7 = 378/126 - Subtract the two like fractions:
270/126 - 378/126 = 270 - 378/126 = -108/126 - After reducing the fraction, the answer is -6/7
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