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Finding the Fourth Proportional to 649.39, 971.69 and 389.54

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Solution

The fourth proportional to 649.39, 971.69 and 389.54 is: 582.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    649.39 : 971.69 = 389.54 : x
  2. Step 2: Convert to fraction form
    649.39/971.69 = 389.54/x
  3. Step 3: Cross multiply
    649.39x = 971.69 × 389.54
  4. Step 4: Simplify right side
    649.39x = 378,512.12
  5. Step 5: Solve for x
    x = 378,512.12/649.39
  6. Step 6: Final answer
    x = 582.87

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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.