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Finding the Fourth Proportional to 638.39, 958.80 and 395.39

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Solution

The fourth proportional to 638.39, 958.80 and 395.39 is: 593.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.39 : 958.80 = 395.39 : x
  2. Step 2: Convert to fraction form
    638.39/958.80 = 395.39/x
  3. Step 3: Cross multiply
    638.39x = 958.80 × 395.39
  4. Step 4: Simplify right side
    638.39x = 379,099.93
  5. Step 5: Solve for x
    x = 379,099.93/638.39
  6. Step 6: Final answer
    x = 593.84

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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.