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Finding the Fourth Proportional to 398.39, 597.87 and 206.15

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Solution

The fourth proportional to 398.39, 597.87 and 206.15 is: 309.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.39 : 597.87 = 206.15 : x
  2. Step 2: Convert to fraction form
    398.39/597.87 = 206.15/x
  3. Step 3: Cross multiply
    398.39x = 597.87 × 206.15
  4. Step 4: Simplify right side
    398.39x = 123,247.91
  5. Step 5: Solve for x
    x = 123,247.91/398.39
  6. Step 6: Final answer
    x = 309.37

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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.