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Finding the Fourth Proportional to 426.28, 638.14 and 317.80

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Solution

The fourth proportional to 426.28, 638.14 and 317.80 is: 475.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    426.28 : 638.14 = 317.80 : x
  2. Step 2: Convert to fraction form
    426.28/638.14 = 317.80/x
  3. Step 3: Cross multiply
    426.28x = 638.14 × 317.80
  4. Step 4: Simplify right side
    426.28x = 202,800.89
  5. Step 5: Solve for x
    x = 202,800.89/426.28
  6. Step 6: Final answer
    x = 475.75

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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.