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Finding the Fourth Proportional to 638.12, 957.17 and 205.31

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Solution

The fourth proportional to 638.12, 957.17 and 205.31 is: 307.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.12 : 957.17 = 205.31 : x
  2. Step 2: Convert to fraction form
    638.12/957.17 = 205.31/x
  3. Step 3: Cross multiply
    638.12x = 957.17 × 205.31
  4. Step 4: Simplify right side
    638.12x = 196,512.30
  5. Step 5: Solve for x
    x = 196,512.30/638.12
  6. Step 6: Final answer
    x = 307.96

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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.