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Finding the Fourth Proportional to 339.47, 509.29 and 331.78

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Solution

The fourth proportional to 339.47, 509.29 and 331.78 is: 497.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    339.47 : 509.29 = 331.78 : x
  2. Step 2: Convert to fraction form
    339.47/509.29 = 331.78/x
  3. Step 3: Cross multiply
    339.47x = 509.29 × 331.78
  4. Step 4: Simplify right side
    339.47x = 168,972.24
  5. Step 5: Solve for x
    x = 168,972.24/339.47
  6. Step 6: Final answer
    x = 497.75

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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.