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Finding the Fourth Proportional to 638.71, 957.83 and 205.75

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Solution

The fourth proportional to 638.71, 957.83 and 205.75 is: 308.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.71 : 957.83 = 205.75 : x
  2. Step 2: Convert to fraction form
    638.71/957.83 = 205.75/x
  3. Step 3: Cross multiply
    638.71x = 957.83 × 205.75
  4. Step 4: Simplify right side
    638.71x = 197,072.49
  5. Step 5: Solve for x
    x = 197,072.49/638.71
  6. Step 6: Final answer
    x = 308.55

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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.