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Finding the Fourth Proportional to 638.31, 955.60 and 394.09

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Solution

The fourth proportional to 638.31, 955.60 and 394.09 is: 589.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.31 : 955.60 = 394.09 : x
  2. Step 2: Convert to fraction form
    638.31/955.60 = 394.09/x
  3. Step 3: Cross multiply
    638.31x = 955.60 × 394.09
  4. Step 4: Simplify right side
    638.31x = 376,592.40
  5. Step 5: Solve for x
    x = 376,592.40/638.31
  6. Step 6: Final answer
    x = 589.98

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.