Subtract 28/90 from 21/2
1st number: 10 1/2, 2nd number: 28/90
21/2 - 28/90 is 917/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 90 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 2 × 45 = 90,
21/2 = 21 × 45/2 × 45 = 945/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
28/90 = 28 × 1/90 × 1 = 28/90 - Subtract the two like fractions:
945/90 - 28/90 = 945 - 28/90 = 917/90 - In mixed form: 1017/90
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