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Finding the Fourth Proportional to 640.40, 959.69 and 503.71

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Solution

The fourth proportional to 640.40, 959.69 and 503.71 is: 754.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.40 : 959.69 = 503.71 : x
  2. Step 2: Convert to fraction form
    640.40/959.69 = 503.71/x
  3. Step 3: Cross multiply
    640.40x = 959.69 × 503.71
  4. Step 4: Simplify right side
    640.40x = 483,404.31
  5. Step 5: Solve for x
    x = 483,404.31/640.40
  6. Step 6: Final answer
    x = 754.85

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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.