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Finding the Fourth Proportional to 638.88, 958.30 and 206.02

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Solution

The fourth proportional to 638.88, 958.30 and 206.02 is: 309.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.88 : 958.30 = 206.02 : x
  2. Step 2: Convert to fraction form
    638.88/958.30 = 206.02/x
  3. Step 3: Cross multiply
    638.88x = 958.30 × 206.02
  4. Step 4: Simplify right side
    638.88x = 197,428.97
  5. Step 5: Solve for x
    x = 197,428.97/638.88
  6. Step 6: Final answer
    x = 309.02

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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.