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Finding the Fourth Proportional to 669.35, 923.27 and 420.45

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Solution

The fourth proportional to 669.35, 923.27 and 420.45 is: 579.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    669.35 : 923.27 = 420.45 : x
  2. Step 2: Convert to fraction form
    669.35/923.27 = 420.45/x
  3. Step 3: Cross multiply
    669.35x = 923.27 × 420.45
  4. Step 4: Simplify right side
    669.35x = 388,190.87
  5. Step 5: Solve for x
    x = 388,190.87/669.35
  6. Step 6: Final answer
    x = 579.95

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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.