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Finding the Fourth Proportional to 862.39, 1,292.89 and 306.79

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Solution

The fourth proportional to 862.39, 1,292.89 and 306.79 is: 459.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    862.39 : 1,292.89 = 306.79 : x
  2. Step 2: Convert to fraction form
    862.39/1,292.89 = 306.79/x
  3. Step 3: Cross multiply
    862.39x = 1,292.89 × 306.79
  4. Step 4: Simplify right side
    862.39x = 396,641.72
  5. Step 5: Solve for x
    x = 396,641.72/862.39
  6. Step 6: Final answer
    x = 459.93

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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.