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Finding the Fourth Proportional to 391.39, 585.87 and 288.79

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Solution

The fourth proportional to 391.39, 585.87 and 288.79 is: 432.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.39 : 585.87 = 288.79 : x
  2. Step 2: Convert to fraction form
    391.39/585.87 = 288.79/x
  3. Step 3: Cross multiply
    391.39x = 585.87 × 288.79
  4. Step 4: Simplify right side
    391.39x = 169,193.40
  5. Step 5: Solve for x
    x = 169,193.40/391.39
  6. Step 6: Final answer
    x = 432.29

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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.