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Finding the Fourth Proportional to 339.26, 509.16 and 278.78

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Solution

The fourth proportional to 339.26, 509.16 and 278.78 is: 418.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    339.26 : 509.16 = 278.78 : x
  2. Step 2: Convert to fraction form
    339.26/509.16 = 278.78/x
  3. Step 3: Cross multiply
    339.26x = 509.16 × 278.78
  4. Step 4: Simplify right side
    339.26x = 141,943.62
  5. Step 5: Solve for x
    x = 141,943.62/339.26
  6. Step 6: Final answer
    x = 418.39

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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.