Subtract 3/90 from 21/8
1st number: 2 5/8, 2nd number: 3/90
21/8 - 3/90 is 311/120.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 90 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 8 × 45 = 360,
21/8 = 21 × 45/8 × 45 = 945/360 - Likewise, for the 2nd fraction, since 90 × 4 = 360,
3/90 = 3 × 4/90 × 4 = 12/360 - Subtract the two like fractions:
945/360 - 12/360 = 945 - 12/360 = 933/360 - After reducing the fraction, the answer is 311/120
- In mixed form: 271/120
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