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Finding the Fourth Proportional to 685.10, 945.24 and 423.20

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Solution

The fourth proportional to 685.10, 945.24 and 423.20 is: 583.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    685.10 : 945.24 = 423.20 : x
  2. Step 2: Convert to fraction form
    685.10/945.24 = 423.20/x
  3. Step 3: Cross multiply
    685.10x = 945.24 × 423.20
  4. Step 4: Simplify right side
    685.10x = 400,025.57
  5. Step 5: Solve for x
    x = 400,025.57/685.10
  6. Step 6: Final answer
    x = 583.89

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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.