Subtract 21/20 from 80/18
1st number: 4 8/18, 2nd number: 1 1/20
80/18 - 21/20 is 611/180.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 18 × 10 = 180,
80/18 = 80 × 10/18 × 10 = 800/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
21/20 = 21 × 9/20 × 9 = 189/180 - Subtract the two like fractions:
800/180 - 189/180 = 800 - 189/180 = 611/180 - In mixed form: 371/180
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