Subtract 12/15 from 21/3
1st number: 7 0/3, 2nd number: 12/15
21/3 - 12/15 is 31/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 3 and 15 is 15
Next, find the equivalent fraction of both fractional numbers with denominator 15 - For the 1st fraction, since 3 × 5 = 15,
21/3 = 21 × 5/3 × 5 = 105/15 - Likewise, for the 2nd fraction, since 15 × 1 = 15,
12/15 = 12 × 1/15 × 1 = 12/15 - Subtract the two like fractions:
105/15 - 12/15 = 105 - 12/15 = 93/15 - After reducing the fraction, the answer is 31/5
- In mixed form: 61/5
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