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Finding the Fourth Proportional to 339.78, 509.70 and 262.80

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Solution

The fourth proportional to 339.78, 509.70 and 262.80 is: 394.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    339.78 : 509.70 = 262.80 : x
  2. Step 2: Convert to fraction form
    339.78/509.70 = 262.80/x
  3. Step 3: Cross multiply
    339.78x = 509.70 × 262.80
  4. Step 4: Simplify right side
    339.78x = 133,949.16
  5. Step 5: Solve for x
    x = 133,949.16/339.78
  6. Step 6: Final answer
    x = 394.22

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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.