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Finding the Fourth Proportional to 447.20, 616.80 and 289.80

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Solution

The fourth proportional to 447.20, 616.80 and 289.80 is: 399.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    447.20 : 616.80 = 289.80 : x
  2. Step 2: Convert to fraction form
    447.20/616.80 = 289.80/x
  3. Step 3: Cross multiply
    447.20x = 616.80 × 289.80
  4. Step 4: Simplify right side
    447.20x = 178,748.64
  5. Step 5: Solve for x
    x = 178,748.64/447.20
  6. Step 6: Final answer
    x = 399.71

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.