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Finding the Fourth Proportional to 639.69, 958.46 and 485.43

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Solution

The fourth proportional to 639.69, 958.46 and 485.43 is: 727.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.69 : 958.46 = 485.43 : x
  2. Step 2: Convert to fraction form
    639.69/958.46 = 485.43/x
  3. Step 3: Cross multiply
    639.69x = 958.46 × 485.43
  4. Step 4: Simplify right side
    639.69x = 465,265.24
  5. Step 5: Solve for x
    x = 465,265.24/639.69
  6. Step 6: Final answer
    x = 727.33

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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.