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Finding the Fourth Proportional to 638.86, 958.44 and 313.85

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Solution

The fourth proportional to 638.86, 958.44 and 313.85 is: 470.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.86 : 958.44 = 313.85 : x
  2. Step 2: Convert to fraction form
    638.86/958.44 = 313.85/x
  3. Step 3: Cross multiply
    638.86x = 958.44 × 313.85
  4. Step 4: Simplify right side
    638.86x = 300,806.39
  5. Step 5: Solve for x
    x = 300,806.39/638.86
  6. Step 6: Final answer
    x = 470.85

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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.