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Finding the Fourth Proportional to 398.29, 597.20 and 138.16

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Solution

The fourth proportional to 398.29, 597.20 and 138.16 is: 207.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.29 : 597.20 = 138.16 : x
  2. Step 2: Convert to fraction form
    398.29/597.20 = 138.16/x
  3. Step 3: Cross multiply
    398.29x = 597.20 × 138.16
  4. Step 4: Simplify right side
    398.29x = 82,505.48
  5. Step 5: Solve for x
    x = 82,505.48/398.29
  6. Step 6: Final answer
    x = 207.15

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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.