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Finding the Fourth Proportional to 640.05, 959.46 and 408.29

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Solution

The fourth proportional to 640.05, 959.46 and 408.29 is: 612.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.05 : 959.46 = 408.29 : x
  2. Step 2: Convert to fraction form
    640.05/959.46 = 408.29/x
  3. Step 3: Cross multiply
    640.05x = 959.46 × 408.29
  4. Step 4: Simplify right side
    640.05x = 391,733.13
  5. Step 5: Solve for x
    x = 391,733.13/640.05
  6. Step 6: Final answer
    x = 612.04

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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.