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Finding the Fourth Proportional to 665.20, 997.81 and 299.89

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Solution

The fourth proportional to 665.20, 997.81 and 299.89 is: 449.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.20 : 997.81 = 299.89 : x
  2. Step 2: Convert to fraction form
    665.20/997.81 = 299.89/x
  3. Step 3: Cross multiply
    665.20x = 997.81 × 299.89
  4. Step 4: Simplify right side
    665.20x = 299,233.74
  5. Step 5: Solve for x
    x = 299,233.74/665.20
  6. Step 6: Final answer
    x = 449.84

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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.