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Finding the Fourth Proportional to 640.50, 959.17 and 408.70

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Solution

The fourth proportional to 640.50, 959.17 and 408.70 is: 612.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.50 : 959.17 = 408.70 : x
  2. Step 2: Convert to fraction form
    640.50/959.17 = 408.70/x
  3. Step 3: Cross multiply
    640.50x = 959.17 × 408.70
  4. Step 4: Simplify right side
    640.50x = 392,012.78
  5. Step 5: Solve for x
    x = 392,012.78/640.50
  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.