Subtract 21/9 from 7/15
1st number: 7/15, 2nd number: 2 3/9
7/15 - 21/9 is -28/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 9 is 45
Next, find the equivalent fraction of both fractional numbers with denominator 45 - For the 1st fraction, since 15 × 3 = 45,
7/15 = 7 × 3/15 × 3 = 21/45 - Likewise, for the 2nd fraction, since 9 × 5 = 45,
21/9 = 21 × 5/9 × 5 = 105/45 - Subtract the two like fractions:
21/45 - 105/45 = 21 - 105/45 = -84/45 - After reducing the fraction, the answer is -28/15
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