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Finding the Fourth Proportional to 669.14, 923.78 and 420.51

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Solution

The fourth proportional to 669.14, 923.78 and 420.51 is: 580.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    669.14 : 923.78 = 420.51 : x
  2. Step 2: Convert to fraction form
    669.14/923.78 = 420.51/x
  3. Step 3: Cross multiply
    669.14x = 923.78 × 420.51
  4. Step 4: Simplify right side
    669.14x = 388,456.63
  5. Step 5: Solve for x
    x = 388,456.63/669.14
  6. Step 6: Final answer
    x = 580.54

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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.