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Finding the Fourth Proportional to 500.40, 691.22 and 385.40

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Solution

The fourth proportional to 500.40, 691.22 and 385.40 is: 532.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    500.40 : 691.22 = 385.40 : x
  2. Step 2: Convert to fraction form
    500.40/691.22 = 385.40/x
  3. Step 3: Cross multiply
    500.40x = 691.22 × 385.40
  4. Step 4: Simplify right side
    500.40x = 266,396.19
  5. Step 5: Solve for x
    x = 266,396.19/500.40
  6. Step 6: Final answer
    x = 532.37

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.