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Finding the Fourth Proportional to 639.69, 958.13 and 331.85

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Solution

The fourth proportional to 639.69, 958.13 and 331.85 is: 497.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.69 : 958.13 = 331.85 : x
  2. Step 2: Convert to fraction form
    639.69/958.13 = 331.85/x
  3. Step 3: Cross multiply
    639.69x = 958.13 × 331.85
  4. Step 4: Simplify right side
    639.69x = 317,948.99
  5. Step 5: Solve for x
    x = 317,948.99/639.69
  6. Step 6: Final answer
    x = 497.04

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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.