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Finding the Fourth Proportional to 669.46, 923.80 and 389.70

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Solution

The fourth proportional to 669.46, 923.80 and 389.70 is: 537.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    669.46 : 923.80 = 389.70 : x
  2. Step 2: Convert to fraction form
    669.46/923.80 = 389.70/x
  3. Step 3: Cross multiply
    669.46x = 923.80 × 389.70
  4. Step 4: Simplify right side
    669.46x = 360,004.86
  5. Step 5: Solve for x
    x = 360,004.86/669.46
  6. Step 6: Final answer
    x = 537.75

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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.