What is 1/3 + 1/4 + 1/5?
Answer and explanation
Correct answer: D. 47/60
- Step 1: The lowest common denominator of 3, 4 and 5 is 60. Step 2. 1/3 = 20/60, 1/4 = 15/60 and 1/5 = 12/60. Step 3. 20 + 15 + 12 = 47, so the sum is 47/60. Answer: 47/60. Why not the others: 3/12: This adds the numerators and the denominators separately. 3/60: This adds the numerators over the product of the denominators. 47/120: This uses 120 as a denominator but halves only the denominator when simplifying 94/120.
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