Subtract 20/18 from 45/72
1st number: 45/72, 2nd number: 1 2/18
45/72 - 20/18 is -35/72.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 18 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 72 × 1 = 72,
45/72 = 45 × 1/72 × 1 = 45/72 - Likewise, for the 2nd fraction, since 18 × 4 = 72,
20/18 = 20 × 4/18 × 4 = 80/72 - Subtract the two like fractions:
45/72 - 80/72 = 45 - 80/72 = -35/72
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