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Finding the Fourth Proportional to 669.20, 923.42 and 389.23

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Solution

The fourth proportional to 669.20, 923.42 and 389.23 is: 537.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    669.20 : 923.42 = 389.23 : x
  2. Step 2: Convert to fraction form
    669.20/923.42 = 389.23/x
  3. Step 3: Cross multiply
    669.20x = 923.42 × 389.23
  4. Step 4: Simplify right side
    669.20x = 359,421.43
  5. Step 5: Solve for x
    x = 359,421.43/669.20
  6. Step 6: Final answer
    x = 537.10

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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.