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Finding the Fourth Proportional to 409.12, 613.37 and 213.87

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Solution

The fourth proportional to 409.12, 613.37 and 213.87 is: 320.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    409.12 : 613.37 = 213.87 : x
  2. Step 2: Convert to fraction form
    409.12/613.37 = 213.87/x
  3. Step 3: Cross multiply
    409.12x = 613.37 × 213.87
  4. Step 4: Simplify right side
    409.12x = 131,184.28
  5. Step 5: Solve for x
    x = 131,184.28/409.12
  6. Step 6: Final answer
    x = 320.65

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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.