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Finding the Fourth Proportional to 426.60, 639.50 and 207.09

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Solution

The fourth proportional to 426.60, 639.50 and 207.09 is: 310.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    426.60 : 639.50 = 207.09 : x
  2. Step 2: Convert to fraction form
    426.60/639.50 = 207.09/x
  3. Step 3: Cross multiply
    426.60x = 639.50 × 207.09
  4. Step 4: Simplify right side
    426.60x = 132,433.02
  5. Step 5: Solve for x
    x = 132,433.02/426.60
  6. Step 6: Final answer
    x = 310.44

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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.