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Finding the Fourth Proportional to 398.30, 597.45 and 138.33

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Solution

The fourth proportional to 398.30, 597.45 and 138.33 is: 207.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.30 : 597.45 = 138.33 : x
  2. Step 2: Convert to fraction form
    398.30/597.45 = 138.33/x
  3. Step 3: Cross multiply
    398.30x = 597.45 × 138.33
  4. Step 4: Simplify right side
    398.30x = 82,645.26
  5. Step 5: Solve for x
    x = 82,645.26/398.30
  6. Step 6: Final answer
    x = 207.50

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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.