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Finding the Fourth Proportional to 206.38, 309.29 and 115.12

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Solution

The fourth proportional to 206.38, 309.29 and 115.12 is: 172.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    206.38 : 309.29 = 115.12 : x
  2. Step 2: Convert to fraction form
    206.38/309.29 = 115.12/x
  3. Step 3: Cross multiply
    206.38x = 309.29 × 115.12
  4. Step 4: Simplify right side
    206.38x = 35,605.46
  5. Step 5: Solve for x
    x = 35,605.46/206.38
  6. Step 6: Final answer
    x = 172.52

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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.