Subtract 21/9 from 28/8
1st number: 3 4/8, 2nd number: 2 3/9
28/8 - 21/9 is 7/6.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 9 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 8 × 9 = 72,
28/8 = 28 × 9/8 × 9 = 252/72 - Likewise, for the 2nd fraction, since 9 × 8 = 72,
21/9 = 21 × 8/9 × 8 = 168/72 - Subtract the two like fractions:
252/72 - 168/72 = 252 - 168/72 = 84/72 - After reducing the fraction, the answer is 7/6
- In mixed form: 11/6
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