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Finding the Fourth Proportional to 640.62, 960.29 and 409.77

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Solution

The fourth proportional to 640.62, 960.29 and 409.77 is: 614.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.62 : 960.29 = 409.77 : x
  2. Step 2: Convert to fraction form
    640.62/960.29 = 409.77/x
  3. Step 3: Cross multiply
    640.62x = 960.29 × 409.77
  4. Step 4: Simplify right side
    640.62x = 393,497.52
  5. Step 5: Solve for x
    x = 393,497.52/640.62
  6. Step 6: Final answer
    x = 614.24

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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.