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Finding the Fourth Proportional to 381.05, 571.05 and 216.61

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Solution

The fourth proportional to 381.05, 571.05 and 216.61 is: 324.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    381.05 : 571.05 = 216.61 : x
  2. Step 2: Convert to fraction form
    381.05/571.05 = 216.61/x
  3. Step 3: Cross multiply
    381.05x = 571.05 × 216.61
  4. Step 4: Simplify right side
    381.05x = 123,696.12
  5. Step 5: Solve for x
    x = 123,696.12/381.05
  6. Step 6: Final answer
    x = 324.62

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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.