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Finding the Fourth Proportional to 408.35, 609.24 and 390.39

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Solution

The fourth proportional to 408.35, 609.24 and 390.39 is: 582.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    408.35 : 609.24 = 390.39 : x
  2. Step 2: Convert to fraction form
    408.35/609.24 = 390.39/x
  3. Step 3: Cross multiply
    408.35x = 609.24 × 390.39
  4. Step 4: Simplify right side
    408.35x = 237,841.20
  5. Step 5: Solve for x
    x = 237,841.20/408.35
  6. Step 6: Final answer
    x = 582.45

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.