Subtract 21/9 from 8/5
1st number: 1 3/5, 2nd number: 2 3/9
8/5 - 21/9 is -11/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 9 is 45
Next, find the equivalent fraction of both fractional numbers with denominator 45 - For the 1st fraction, since 5 × 9 = 45,
8/5 = 8 × 9/5 × 9 = 72/45 - Likewise, for the 2nd fraction, since 9 × 5 = 45,
21/9 = 21 × 5/9 × 5 = 105/45 - Subtract the two like fractions:
72/45 - 105/45 = 72 - 105/45 = -33/45 - After reducing the fraction, the answer is -11/15
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