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Finding the Fourth Proportional to 390.92, 585.79 and 308.86

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Solution

The fourth proportional to 390.92, 585.79 and 308.86 is: 462.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.92 : 585.79 = 308.86 : x
  2. Step 2: Convert to fraction form
    390.92/585.79 = 308.86/x
  3. Step 3: Cross multiply
    390.92x = 585.79 × 308.86
  4. Step 4: Simplify right side
    390.92x = 180,924.86
  5. Step 5: Solve for x
    x = 180,924.86/390.92
  6. Step 6: Final answer
    x = 462.82

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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.