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Finding the Fourth Proportional to 217.14, 299.66 and 128.62

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Solution

The fourth proportional to 217.14, 299.66 and 128.62 is: 177.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    217.14 : 299.66 = 128.62 : x
  2. Step 2: Convert to fraction form
    217.14/299.66 = 128.62/x
  3. Step 3: Cross multiply
    217.14x = 299.66 × 128.62
  4. Step 4: Simplify right side
    217.14x = 38,542.27
  5. Step 5: Solve for x
    x = 38,542.27/217.14
  6. Step 6: Final answer
    x = 177.50

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.