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Finding the Fourth Proportional to 640.69, 961.03 and 255.94

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Solution

The fourth proportional to 640.69, 961.03 and 255.94 is: 383.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.69 : 961.03 = 255.94 : x
  2. Step 2: Convert to fraction form
    640.69/961.03 = 255.94/x
  3. Step 3: Cross multiply
    640.69x = 961.03 × 255.94
  4. Step 4: Simplify right side
    640.69x = 245,963.94
  5. Step 5: Solve for x
    x = 245,963.94/640.69
  6. Step 6: Final answer
    x = 383.91

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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.