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Finding the Fourth Proportional to 398.08, 597.12 and 138.08

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Solution

The fourth proportional to 398.08, 597.12 and 138.08 is: 207.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.08 : 597.12 = 138.08 : x
  2. Step 2: Convert to fraction form
    398.08/597.12 = 138.08/x
  3. Step 3: Cross multiply
    398.08x = 597.12 × 138.08
  4. Step 4: Simplify right side
    398.08x = 82,450.33
  5. Step 5: Solve for x
    x = 82,450.33/398.08
  6. Step 6: Final answer
    x = 207.12

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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.