Subtract 54/21 from 45/72
1st number: 45/72, 2nd number: 2 12/21
45/72 - 54/21 is -109/56.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 21 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 72 × 7 = 504,
45/72 = 45 × 7/72 × 7 = 315/504 - Likewise, for the 2nd fraction, since 21 × 24 = 504,
54/21 = 54 × 24/21 × 24 = 1296/504 - Subtract the two like fractions:
315/504 - 1296/504 = 315 - 1296/504 = -981/504 - After reducing the fraction, the answer is -109/56
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