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Finding the Fourth Proportional to 864.09, 1,296.39 and 343.79

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Solution

The fourth proportional to 864.09, 1,296.39 and 343.79 is: 515.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    864.09 : 1,296.39 = 343.79 : x
  2. Step 2: Convert to fraction form
    864.09/1,296.39 = 343.79/x
  3. Step 3: Cross multiply
    864.09x = 1,296.39 × 343.79
  4. Step 4: Simplify right side
    864.09x = 445,691.91
  5. Step 5: Solve for x
    x = 445,691.91/864.09
  6. Step 6: Final answer
    x = 515.79

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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.