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Finding the Fourth Proportional to 419.23, 628.17 and 288.78

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Solution

The fourth proportional to 419.23, 628.17 and 288.78 is: 432.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.23 : 628.17 = 288.78 : x
  2. Step 2: Convert to fraction form
    419.23/628.17 = 288.78/x
  3. Step 3: Cross multiply
    419.23x = 628.17 × 288.78
  4. Step 4: Simplify right side
    419.23x = 181,404.65
  5. Step 5: Solve for x
    x = 181,404.65/419.23
  6. Step 6: Final answer
    x = 432.71

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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.