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Finding the Fourth Proportional to 638.20, 965.41 and 638.20

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Solution

The fourth proportional to 638.20, 965.41 and 638.20 is: 965.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.20 : 965.41 = 638.20 : x
  2. Step 2: Convert to fraction form
    638.20/965.41 = 638.20/x
  3. Step 3: Cross multiply
    638.20x = 965.41 × 638.20
  4. Step 4: Simplify right side
    638.20x = 616,124.66
  5. Step 5: Solve for x
    x = 616,124.66/638.20
  6. Step 6: Final answer
    x = 965.41

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.