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Finding the Fourth Proportional to 665.43, 998.07 and 387.94

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Solution

The fourth proportional to 665.43, 998.07 and 387.94 is: 581.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.43 : 998.07 = 387.94 : x
  2. Step 2: Convert to fraction form
    665.43/998.07 = 387.94/x
  3. Step 3: Cross multiply
    665.43x = 998.07 × 387.94
  4. Step 4: Simplify right side
    665.43x = 387,189.34
  5. Step 5: Solve for x
    x = 387,189.34/665.43
  6. Step 6: Final answer
    x = 581.86

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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.