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Finding the Fourth Proportional to 638.81, 958.21 and 206.27

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Solution

The fourth proportional to 638.81, 958.21 and 206.27 is: 309.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.81 : 958.21 = 206.27 : x
  2. Step 2: Convert to fraction form
    638.81/958.21 = 206.27/x
  3. Step 3: Cross multiply
    638.81x = 958.21 × 206.27
  4. Step 4: Simplify right side
    638.81x = 197,644.67
  5. Step 5: Solve for x
    x = 197,644.67/638.81
  6. Step 6: Final answer
    x = 309.40

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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.