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Finding the Fourth Proportional to 398.38, 597.42 and 215.74

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Solution

The fourth proportional to 398.38, 597.42 and 215.74 is: 323.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.38 : 597.42 = 215.74 : x
  2. Step 2: Convert to fraction form
    398.38/597.42 = 215.74/x
  3. Step 3: Cross multiply
    398.38x = 597.42 × 215.74
  4. Step 4: Simplify right side
    398.38x = 128,887.39
  5. Step 5: Solve for x
    x = 128,887.39/398.38
  6. Step 6: Final answer
    x = 323.53

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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.