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Finding the Fourth Proportional to 638.50, 957.71 and 205.66

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Solution

The fourth proportional to 638.50, 957.71 and 205.66 is: 308.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.50 : 957.71 = 205.66 : x
  2. Step 2: Convert to fraction form
    638.50/957.71 = 205.66/x
  3. Step 3: Cross multiply
    638.50x = 957.71 × 205.66
  4. Step 4: Simplify right side
    638.50x = 196,960.76
  5. Step 5: Solve for x
    x = 196,960.76/638.50
  6. Step 6: Final answer
    x = 308.48

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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.