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Finding the Fourth Proportional to 339.85, 509.68 and 285.36

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Solution

The fourth proportional to 339.85, 509.68 and 285.36 is: 427.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    339.85 : 509.68 = 285.36 : x
  2. Step 2: Convert to fraction form
    339.85/509.68 = 285.36/x
  3. Step 3: Cross multiply
    339.85x = 509.68 × 285.36
  4. Step 4: Simplify right side
    339.85x = 145,442.28
  5. Step 5: Solve for x
    x = 145,442.28/339.85
  6. Step 6: Final answer
    x = 427.96

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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.