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Finding the Fourth Proportional to 638.20, 957.02 and 205.40

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Solution

The fourth proportional to 638.20, 957.02 and 205.40 is: 308.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.20 : 957.02 = 205.40 : x
  2. Step 2: Convert to fraction form
    638.20/957.02 = 205.40/x
  3. Step 3: Cross multiply
    638.20x = 957.02 × 205.40
  4. Step 4: Simplify right side
    638.20x = 196,571.91
  5. Step 5: Solve for x
    x = 196,571.91/638.20
  6. Step 6: Final answer
    x = 308.01

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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.