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Finding the Fourth Proportional to 638.20, 958.67 and 540.90

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Solution

The fourth proportional to 638.20, 958.67 and 540.90 is: 812.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.20 : 958.67 = 540.90 : x
  2. Step 2: Convert to fraction form
    638.20/958.67 = 540.90/x
  3. Step 3: Cross multiply
    638.20x = 958.67 × 540.90
  4. Step 4: Simplify right side
    638.20x = 518,544.60
  5. Step 5: Solve for x
    x = 518,544.60/638.20
  6. Step 6: Final answer
    x = 812.51

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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.