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Finding the Fourth Proportional to 288.38, 431.78 and 219.71

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Solution

The fourth proportional to 288.38, 431.78 and 219.71 is: 328.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    288.38 : 431.78 = 219.71 : x
  2. Step 2: Convert to fraction form
    288.38/431.78 = 219.71/x
  3. Step 3: Cross multiply
    288.38x = 431.78 × 219.71
  4. Step 4: Simplify right side
    288.38x = 94,863.13
  5. Step 5: Solve for x
    x = 94,863.13/288.38
  6. Step 6: Final answer
    x = 328.96

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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.