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Finding the Fourth Proportional to 344.78, 517.26 and 139.31

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Solution

The fourth proportional to 344.78, 517.26 and 139.31 is: 209.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    344.78 : 517.26 = 139.31 : x
  2. Step 2: Convert to fraction form
    344.78/517.26 = 139.31/x
  3. Step 3: Cross multiply
    344.78x = 517.26 × 139.31
  4. Step 4: Simplify right side
    344.78x = 72,059.49
  5. Step 5: Solve for x
    x = 72,059.49/344.78
  6. Step 6: Final answer
    x = 209.00

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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.