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Finding the Fourth Proportional to 638.88, 958.45 and 206.07

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Solution

The fourth proportional to 638.88, 958.45 and 206.07 is: 309.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.88 : 958.45 = 206.07 : x
  2. Step 2: Convert to fraction form
    638.88/958.45 = 206.07/x
  3. Step 3: Cross multiply
    638.88x = 958.45 × 206.07
  4. Step 4: Simplify right side
    638.88x = 197,507.79
  5. Step 5: Solve for x
    x = 197,507.79/638.88
  6. Step 6: Final answer
    x = 309.15

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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.