Subtract 21/90 from 80/18
1st number: 4 8/18, 2nd number: 21/90
80/18 - 21/90 is 379/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 90 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 18 × 5 = 90,
80/18 = 80 × 5/18 × 5 = 400/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
21/90 = 21 × 1/90 × 1 = 21/90 - Subtract the two like fractions:
400/90 - 21/90 = 400 - 21/90 = 379/90 - In mixed form: 419/90
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