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Finding the Fourth Proportional to 665.28, 997.89 and 318.85

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Solution

The fourth proportional to 665.28, 997.89 and 318.85 is: 478.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.28 : 997.89 = 318.85 : x
  2. Step 2: Convert to fraction form
    665.28/997.89 = 318.85/x
  3. Step 3: Cross multiply
    665.28x = 997.89 × 318.85
  4. Step 4: Simplify right side
    665.28x = 318,177.23
  5. Step 5: Solve for x
    x = 318,177.23/665.28
  6. Step 6: Final answer
    x = 478.26

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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.