Subtract 1/90 from 21/20
1st number: 1 1/20, 2nd number: 1/90
21/20 - 1/90 is 187/180.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 90 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
21/20 = 21 × 9/20 × 9 = 189/180 - Likewise, for the 2nd fraction, since 90 × 2 = 180,
1/90 = 1 × 2/90 × 2 = 2/180 - Subtract the two like fractions:
189/180 - 2/180 = 189 - 2/180 = 187/180 - In mixed form: 17/180
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