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Finding the Fourth Proportional to 638.91, 958.55 and 206.10

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Solution

The fourth proportional to 638.91, 958.55 and 206.10 is: 309.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.91 : 958.55 = 206.10 : x
  2. Step 2: Convert to fraction form
    638.91/958.55 = 206.10/x
  3. Step 3: Cross multiply
    638.91x = 958.55 × 206.10
  4. Step 4: Simplify right side
    638.91x = 197,556.12
  5. Step 5: Solve for x
    x = 197,556.12/638.91
  6. Step 6: Final answer
    x = 309.21

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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.