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Finding the Fourth Proportional to 209.38, 288.81 and 130.71

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Solution

The fourth proportional to 209.38, 288.81 and 130.71 is: 180.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    209.38 : 288.81 = 130.71 : x
  2. Step 2: Convert to fraction form
    209.38/288.81 = 130.71/x
  3. Step 3: Cross multiply
    209.38x = 288.81 × 130.71
  4. Step 4: Simplify right side
    209.38x = 37,750.36
  5. Step 5: Solve for x
    x = 37,750.36/209.38
  6. Step 6: Final answer
    x = 180.30

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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.