Subtract 4/90 from 21/18
1st number: 1 3/18, 2nd number: 4/90
21/18 - 4/90 is 101/90.
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,
21/18 = 21 × 5/18 × 5 = 105/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
4/90 = 4 × 1/90 × 1 = 4/90 - Subtract the two like fractions:
105/90 - 4/90 = 105 - 4/90 = 101/90 - In mixed form: 111/90
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