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Finding the Fourth Proportional to 470.30, 705.39 and 213.78

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Solution

The fourth proportional to 470.30, 705.39 and 213.78 is: 320.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    470.30 : 705.39 = 213.78 : x
  2. Step 2: Convert to fraction form
    470.30/705.39 = 213.78/x
  3. Step 3: Cross multiply
    470.30x = 705.39 × 213.78
  4. Step 4: Simplify right side
    470.30x = 150,798.27
  5. Step 5: Solve for x
    x = 150,798.27/470.30
  6. Step 6: Final answer
    x = 320.64

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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.