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Finding the Fourth Proportional to 408.08, 612.39 and 215.84

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Solution

The fourth proportional to 408.08, 612.39 and 215.84 is: 323.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    408.08 : 612.39 = 215.84 : x
  2. Step 2: Convert to fraction form
    408.08/612.39 = 215.84/x
  3. Step 3: Cross multiply
    408.08x = 612.39 × 215.84
  4. Step 4: Simplify right side
    408.08x = 132,178.26
  5. Step 5: Solve for x
    x = 132,178.26/408.08
  6. Step 6: Final answer
    x = 323.90

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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.