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Finding the Fourth Proportional to 439.40, 652.60 and 431.30

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Solution

The fourth proportional to 439.40, 652.60 and 431.30 is: 640.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    439.40 : 652.60 = 431.30 : x
  2. Step 2: Convert to fraction form
    439.40/652.60 = 431.30/x
  3. Step 3: Cross multiply
    439.40x = 652.60 × 431.30
  4. Step 4: Simplify right side
    439.40x = 281,466.38
  5. Step 5: Solve for x
    x = 281,466.38/439.40
  6. Step 6: Final answer
    x = 640.57

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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.