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Finding the Fourth Proportional to 658.80, 908.78 and 419.09

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Solution

The fourth proportional to 658.80, 908.78 and 419.09 is: 578.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    658.80 : 908.78 = 419.09 : x
  2. Step 2: Convert to fraction form
    658.80/908.78 = 419.09/x
  3. Step 3: Cross multiply
    658.80x = 908.78 × 419.09
  4. Step 4: Simplify right side
    658.80x = 380,853.97
  5. Step 5: Solve for x
    x = 380,853.97/658.80
  6. Step 6: Final answer
    x = 578.10

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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.