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Finding the Fourth Proportional to 487.39, 731.09 and 213.42

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Solution

The fourth proportional to 487.39, 731.09 and 213.42 is: 320.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    487.39 : 731.09 = 213.42 : x
  2. Step 2: Convert to fraction form
    487.39/731.09 = 213.42/x
  3. Step 3: Cross multiply
    487.39x = 731.09 × 213.42
  4. Step 4: Simplify right side
    487.39x = 156,030.57
  5. Step 5: Solve for x
    x = 156,030.57/487.39
  6. Step 6: Final answer
    x = 320.13

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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.