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Finding the Fourth Proportional to 638.63, 958.26 and 345.81

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Solution

The fourth proportional to 638.63, 958.26 and 345.81 is: 518.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.63 : 958.26 = 345.81 : x
  2. Step 2: Convert to fraction form
    638.63/958.26 = 345.81/x
  3. Step 3: Cross multiply
    638.63x = 958.26 × 345.81
  4. Step 4: Simplify right side
    638.63x = 331,380.78
  5. Step 5: Solve for x
    x = 331,380.78/638.63
  6. Step 6: Final answer
    x = 518.89

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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.