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Finding the Fourth Proportional to 669.31, 923.49 and 389.43

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Solution

The fourth proportional to 669.31, 923.49 and 389.43 is: 537.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    669.31 : 923.49 = 389.43 : x
  2. Step 2: Convert to fraction form
    669.31/923.49 = 389.43/x
  3. Step 3: Cross multiply
    669.31x = 923.49 × 389.43
  4. Step 4: Simplify right side
    669.31x = 359,634.71
  5. Step 5: Solve for x
    x = 359,634.71/669.31
  6. Step 6: Final answer
    x = 537.32

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.