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Finding the Fourth Proportional to 487.47, 731.09 and 279.17

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Solution

The fourth proportional to 487.47, 731.09 and 279.17 is: 418.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    487.47 : 731.09 = 279.17 : x
  2. Step 2: Convert to fraction form
    487.47/731.09 = 279.17/x
  3. Step 3: Cross multiply
    487.47x = 731.09 × 279.17
  4. Step 4: Simplify right side
    487.47x = 204,095.44
  5. Step 5: Solve for x
    x = 204,095.44/487.47
  6. Step 6: Final answer
    x = 418.68

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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.