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Finding the Fourth Proportional to 383.20, 528.68 and 285.12

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Solution

The fourth proportional to 383.20, 528.68 and 285.12 is: 393.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    383.20 : 528.68 = 285.12 : x
  2. Step 2: Convert to fraction form
    383.20/528.68 = 285.12/x
  3. Step 3: Cross multiply
    383.20x = 528.68 × 285.12
  4. Step 4: Simplify right side
    383.20x = 150,737.24
  5. Step 5: Solve for x
    x = 150,737.24/383.20
  6. Step 6: Final answer
    x = 393.36

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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.