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Finding the Third Proportional to 311 and 647

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Solution

The third proportional to 311 and 647 is: 1,346.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    311 : 647 = 647 : x
  2. Step 2: Convert to fraction form
    311/647 = 647/x
  3. Step 3: Cross multiply
    311x = 647 × 647
  4. Step 4: Simplify right side
    311x = 418,609
  5. Step 5: Solve for x
    x = 418,609/311
  6. Step 6: Final answer
    x = 1,346.01

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Why These Related Problems?

These problems maintain the same ratio (2.08) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.