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Finding the Fourth Proportional to 864.38, 1,295.88 and 308.78

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Solution

The fourth proportional to 864.38, 1,295.88 and 308.78 is: 462.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    864.38 : 1,295.88 = 308.78 : x
  2. Step 2: Convert to fraction form
    864.38/1,295.88 = 308.78/x
  3. Step 3: Cross multiply
    864.38x = 1,295.88 × 308.78
  4. Step 4: Simplify right side
    864.38x = 400,141.83
  5. Step 5: Solve for x
    x = 400,141.83/864.38
  6. Step 6: Final answer
    x = 462.92

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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.