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Finding the Fourth Proportional to 519.50, 778.68 and 458.78

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Solution

The fourth proportional to 519.50, 778.68 and 458.78 is: 687.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    519.50 : 778.68 = 458.78 : x
  2. Step 2: Convert to fraction form
    519.50/778.68 = 458.78/x
  3. Step 3: Cross multiply
    519.50x = 778.68 × 458.78
  4. Step 4: Simplify right side
    519.50x = 357,242.81
  5. Step 5: Solve for x
    x = 357,242.81/519.50
  6. Step 6: Final answer
    x = 687.67

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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.