Subtract 20/28 from 45/72
45/72 - 20/28 is -5/56.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 28 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 28 × 18 = 504,
20/28 = 20 × 18/28 × 18 = 360/504 - Subtract the two like fractions:
315/504 - 360/504 = 315 - 360/504 = -45/504 - After reducing the fraction, the answer is -5/56
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