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Finding the Fourth Proportional to 638.86, 958.40 and 395.05

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Solution

The fourth proportional to 638.86, 958.40 and 395.05 is: 592.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.86 : 958.40 = 395.05 : x
  2. Step 2: Convert to fraction form
    638.86/958.40 = 395.05/x
  3. Step 3: Cross multiply
    638.86x = 958.40 × 395.05
  4. Step 4: Simplify right side
    638.86x = 378,615.92
  5. Step 5: Solve for x
    x = 378,615.92/638.86
  6. Step 6: Final answer
    x = 592.64

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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.