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Finding the Fourth Proportional to 640.43, 960.29 and 409.17

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Solution

The fourth proportional to 640.43, 960.29 and 409.17 is: 613.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.43 : 960.29 = 409.17 : x
  2. Step 2: Convert to fraction form
    640.43/960.29 = 409.17/x
  3. Step 3: Cross multiply
    640.43x = 960.29 × 409.17
  4. Step 4: Simplify right side
    640.43x = 392,923.41
  5. Step 5: Solve for x
    x = 392,923.41/640.43
  6. Step 6: Final answer
    x = 613.53

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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.