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Finding the Fourth Proportional to 640.39, 960.51 and 396.85

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Solution

The fourth proportional to 640.39, 960.51 and 396.85 is: 595.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.39 : 960.51 = 396.85 : x
  2. Step 2: Convert to fraction form
    640.39/960.51 = 396.85/x
  3. Step 3: Cross multiply
    640.39x = 960.51 × 396.85
  4. Step 4: Simplify right side
    640.39x = 381,178.39
  5. Step 5: Solve for x
    x = 381,178.39/640.39
  6. Step 6: Final answer
    x = 595.23

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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.