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Finding the Fourth Proportional to 338.60, 509.10 and 285.80

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Solution

The fourth proportional to 338.60, 509.10 and 285.80 is: 429.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    338.60 : 509.10 = 285.80 : x
  2. Step 2: Convert to fraction form
    338.60/509.10 = 285.80/x
  3. Step 3: Cross multiply
    338.60x = 509.10 × 285.80
  4. Step 4: Simplify right side
    338.60x = 145,500.78
  5. Step 5: Solve for x
    x = 145,500.78/338.60
  6. Step 6: Final answer
    x = 429.71

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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.