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Finding the Fourth Proportional to 381.21, 571.33 and 243.91

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Solution

The fourth proportional to 381.21, 571.33 and 243.91 is: 365.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    381.21 : 571.33 = 243.91 : x
  2. Step 2: Convert to fraction form
    381.21/571.33 = 243.91/x
  3. Step 3: Cross multiply
    381.21x = 571.33 × 243.91
  4. Step 4: Simplify right side
    381.21x = 139,353.10
  5. Step 5: Solve for x
    x = 139,353.10/381.21
  6. Step 6: Final answer
    x = 365.55

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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.