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Finding the Fourth Proportional to 659.57, 989.47 and 269.78

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Solution

The fourth proportional to 659.57, 989.47 and 269.78 is: 404.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    659.57 : 989.47 = 269.78 : x
  2. Step 2: Convert to fraction form
    659.57/989.47 = 269.78/x
  3. Step 3: Cross multiply
    659.57x = 989.47 × 269.78
  4. Step 4: Simplify right side
    659.57x = 266,937.87
  5. Step 5: Solve for x
    x = 266,937.87/659.57
  6. Step 6: Final answer
    x = 404.71

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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.