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Finding the Fourth Proportional to 347.60, 521.49 and 128.39

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Solution

The fourth proportional to 347.60, 521.49 and 128.39 is: 192.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    347.60 : 521.49 = 128.39 : x
  2. Step 2: Convert to fraction form
    347.60/521.49 = 128.39/x
  3. Step 3: Cross multiply
    347.60x = 521.49 × 128.39
  4. Step 4: Simplify right side
    347.60x = 66,951.25
  5. Step 5: Solve for x
    x = 66,951.25/347.60
  6. Step 6: Final answer
    x = 192.61

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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.