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Finding the Fourth Proportional to 669.16, 923.12 and 420.36

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Solution

The fourth proportional to 669.16, 923.12 and 420.36 is: 579.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    669.16 : 923.12 = 420.36 : x
  2. Step 2: Convert to fraction form
    669.16/923.12 = 420.36/x
  3. Step 3: Cross multiply
    669.16x = 923.12 × 420.36
  4. Step 4: Simplify right side
    669.16x = 388,042.72
  5. Step 5: Solve for x
    x = 388,042.72/669.16
  6. Step 6: Final answer
    x = 579.90

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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.