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Finding the Fourth Proportional to 638.28, 957.56 and 205.44

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Solution

The fourth proportional to 638.28, 957.56 and 205.44 is: 308.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.28 : 957.56 = 205.44 : x
  2. Step 2: Convert to fraction form
    638.28/957.56 = 205.44/x
  3. Step 3: Cross multiply
    638.28x = 957.56 × 205.44
  4. Step 4: Simplify right side
    638.28x = 196,721.13
  5. Step 5: Solve for x
    x = 196,721.13/638.28
  6. Step 6: Final answer
    x = 308.21

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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.