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Finding the Fourth Proportional to 640.83, 961.55 and 381.35

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Solution

The fourth proportional to 640.83, 961.55 and 381.35 is: 572.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.83 : 961.55 = 381.35 : x
  2. Step 2: Convert to fraction form
    640.83/961.55 = 381.35/x
  3. Step 3: Cross multiply
    640.83x = 961.55 × 381.35
  4. Step 4: Simplify right side
    640.83x = 366,680.38
  5. Step 5: Solve for x
    x = 366,680.38/640.83
  6. Step 6: Final answer
    x = 572.20

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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.