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Finding the Fourth Proportional to 578.81, 868.39 and 213.60

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Solution

The fourth proportional to 578.81, 868.39 and 213.60 is: 320.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    578.81 : 868.39 = 213.60 : x
  2. Step 2: Convert to fraction form
    578.81/868.39 = 213.60/x
  3. Step 3: Cross multiply
    578.81x = 868.39 × 213.60
  4. Step 4: Simplify right side
    578.81x = 185,490.83
  5. Step 5: Solve for x
    x = 185,490.83/578.81
  6. Step 6: Final answer
    x = 320.47

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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.