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Finding the Fourth Proportional to 638.65, 958.11 and 205.75

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Solution

The fourth proportional to 638.65, 958.11 and 205.75 is: 308.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.65 : 958.11 = 205.75 : x
  2. Step 2: Convert to fraction form
    638.65/958.11 = 205.75/x
  3. Step 3: Cross multiply
    638.65x = 958.11 × 205.75
  4. Step 4: Simplify right side
    638.65x = 197,131.13
  5. Step 5: Solve for x
    x = 197,131.13/638.65
  6. Step 6: Final answer
    x = 308.67

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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.