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Finding the Fourth Proportional to 344.85, 517.28 and 128.39

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Solution

The fourth proportional to 344.85, 517.28 and 128.39 is: 192.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    344.85 : 517.28 = 128.39 : x
  2. Step 2: Convert to fraction form
    344.85/517.28 = 128.39/x
  3. Step 3: Cross multiply
    344.85x = 517.28 × 128.39
  4. Step 4: Simplify right side
    344.85x = 66,410.35
  5. Step 5: Solve for x
    x = 66,410.35/344.85
  6. Step 6: Final answer
    x = 192.58

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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.