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Finding the Fourth Proportional to 438.69, 658.21 and 207.64

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Solution

The fourth proportional to 438.69, 658.21 and 207.64 is: 311.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    438.69 : 658.21 = 207.64 : x
  2. Step 2: Convert to fraction form
    438.69/658.21 = 207.64/x
  3. Step 3: Cross multiply
    438.69x = 658.21 × 207.64
  4. Step 4: Simplify right side
    438.69x = 136,670.72
  5. Step 5: Solve for x
    x = 136,670.72/438.69
  6. Step 6: Final answer
    x = 311.54

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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.