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Finding the Fourth Proportional to 638.49, 957.72 and 205.64

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Solution

The fourth proportional to 638.49, 957.72 and 205.64 is: 308.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.49 : 957.72 = 205.64 : x
  2. Step 2: Convert to fraction form
    638.49/957.72 = 205.64/x
  3. Step 3: Cross multiply
    638.49x = 957.72 × 205.64
  4. Step 4: Simplify right side
    638.49x = 196,940.75
  5. Step 5: Solve for x
    x = 196,940.75/638.49
  6. Step 6: Final answer
    x = 308.45

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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.