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Finding the Fourth Proportional to 685.07, 945.39 and 423.09

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Solution

The fourth proportional to 685.07, 945.39 and 423.09 is: 583.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    685.07 : 945.39 = 423.09 : x
  2. Step 2: Convert to fraction form
    685.07/945.39 = 423.09/x
  3. Step 3: Cross multiply
    685.07x = 945.39 × 423.09
  4. Step 4: Simplify right side
    685.07x = 399,978.21
  5. Step 5: Solve for x
    x = 399,978.21/685.07
  6. Step 6: Final answer
    x = 583.85

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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.