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Finding the Fourth Proportional to 640.11, 959.38 and 331.79

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Solution

The fourth proportional to 640.11, 959.38 and 331.79 is: 497.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.11 : 959.38 = 331.79 : x
  2. Step 2: Convert to fraction form
    640.11/959.38 = 331.79/x
  3. Step 3: Cross multiply
    640.11x = 959.38 × 331.79
  4. Step 4: Simplify right side
    640.11x = 318,309.46
  5. Step 5: Solve for x
    x = 318,309.46/640.11
  6. Step 6: Final answer
    x = 497.28

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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.