Subtract 81/16 from 20/45
1st number: 20/45, 2nd number: 5 1/16
20/45 - 81/16 is -665/144.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 16 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 45 × 16 = 720,
20/45 = 20 × 16/45 × 16 = 320/720 - Likewise, for the 2nd fraction, since 16 × 45 = 720,
81/16 = 81 × 45/16 × 45 = 3645/720 - Subtract the two like fractions:
320/720 - 3645/720 = 320 - 3645/720 = -3325/720 - After reducing the fraction, the answer is -665/144
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