Subtract 90/15 from 81/20
1st number: 4 1/20, 2nd number: 6 0/15
81/20 - 90/15 is -39/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 15 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 20 × 3 = 60,
81/20 = 81 × 3/20 × 3 = 243/60 - Likewise, for the 2nd fraction, since 15 × 4 = 60,
90/15 = 90 × 4/15 × 4 = 360/60 - Subtract the two like fractions:
243/60 - 360/60 = 243 - 360/60 = -117/60 - After reducing the fraction, the answer is -39/20
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