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Finding the Fourth Proportional to 640.88, 961.86 and 397.61

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Solution

The fourth proportional to 640.88, 961.86 and 397.61 is: 596.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.88 : 961.86 = 397.61 : x
  2. Step 2: Convert to fraction form
    640.88/961.86 = 397.61/x
  3. Step 3: Cross multiply
    640.88x = 961.86 × 397.61
  4. Step 4: Simplify right side
    640.88x = 382,440.35
  5. Step 5: Solve for x
    x = 382,440.35/640.88
  6. Step 6: Final answer
    x = 596.75

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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.