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Finding the Fourth Proportional to 685.01, 945.24 and 405.20

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Solution

The fourth proportional to 685.01, 945.24 and 405.20 is: 559.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    685.01 : 945.24 = 405.20 : x
  2. Step 2: Convert to fraction form
    685.01/945.24 = 405.20/x
  3. Step 3: Cross multiply
    685.01x = 945.24 × 405.20
  4. Step 4: Simplify right side
    685.01x = 383,006.52
  5. Step 5: Solve for x
    x = 383,006.52/685.01
  6. Step 6: Final answer
    x = 559.13

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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.