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Finding the Fourth Proportional to 638.95, 958.43 and 206.11

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Solution

The fourth proportional to 638.95, 958.43 and 206.11 is: 309.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.95 : 958.43 = 206.11 : x
  2. Step 2: Convert to fraction form
    638.95/958.43 = 206.11/x
  3. Step 3: Cross multiply
    638.95x = 958.43 × 206.11
  4. Step 4: Simplify right side
    638.95x = 197,540.98
  5. Step 5: Solve for x
    x = 197,540.98/638.95
  6. Step 6: Final answer
    x = 309.17

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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.