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Finding the Fourth Proportional to 517.85, 776.81 and 209.70

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Solution

The fourth proportional to 517.85, 776.81 and 209.70 is: 314.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    517.85 : 776.81 = 209.70 : x
  2. Step 2: Convert to fraction form
    517.85/776.81 = 209.70/x
  3. Step 3: Cross multiply
    517.85x = 776.81 × 209.70
  4. Step 4: Simplify right side
    517.85x = 162,897.06
  5. Step 5: Solve for x
    x = 162,897.06/517.85
  6. Step 6: Final answer
    x = 314.56

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.