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Finding the Fourth Proportional to 217.28, 301.19 and 209.72

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Solution

The fourth proportional to 217.28, 301.19 and 209.72 is: 290.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    217.28 : 301.19 = 209.72 : x
  2. Step 2: Convert to fraction form
    217.28/301.19 = 209.72/x
  3. Step 3: Cross multiply
    217.28x = 301.19 × 209.72
  4. Step 4: Simplify right side
    217.28x = 63,165.27
  5. Step 5: Solve for x
    x = 63,165.27/217.28
  6. Step 6: Final answer
    x = 290.71

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.