Subtract 80/18 from 81/30
1st number: 2 21/30, 2nd number: 4 8/18
81/30 - 80/18 is -157/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 18 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 30 × 3 = 90,
81/30 = 81 × 3/30 × 3 = 243/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
80/18 = 80 × 5/18 × 5 = 400/90 - Subtract the two like fractions:
243/90 - 400/90 = 243 - 400/90 = -157/90
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