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Finding the Fourth Proportional to 438.10, 658.05 and 422.80

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Solution

The fourth proportional to 438.10, 658.05 and 422.80 is: 635.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    438.10 : 658.05 = 422.80 : x
  2. Step 2: Convert to fraction form
    438.10/658.05 = 422.80/x
  3. Step 3: Cross multiply
    438.10x = 658.05 × 422.80
  4. Step 4: Simplify right side
    438.10x = 278,223.54
  5. Step 5: Solve for x
    x = 278,223.54/438.10
  6. Step 6: Final answer
    x = 635.07

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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.