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Finding the Fourth Proportional to 640.86, 959.67 and 397.86

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Solution

The fourth proportional to 640.86, 959.67 and 397.86 is: 595.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.86 : 959.67 = 397.86 : x
  2. Step 2: Convert to fraction form
    640.86/959.67 = 397.86/x
  3. Step 3: Cross multiply
    640.86x = 959.67 × 397.86
  4. Step 4: Simplify right side
    640.86x = 381,814.31
  5. Step 5: Solve for x
    x = 381,814.31/640.86
  6. Step 6: Final answer
    x = 595.78

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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.