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Finding the Third Proportional to 638.91 and 906.05

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Solution

The third proportional to 638.91 and 906.05 is: 1,284.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.91 : 906.05 = 906.05 : x
  2. Step 2: Convert to fraction form
    638.91/906.05 = 906.05/x
  3. Step 3: Cross multiply
    638.91x = 906.05 × 906.05
  4. Step 4: Simplify right side
    638.91x = 820,920.94
  5. Step 5: Solve for x
    x = 820,920.94/638.91
  6. Step 6: Final answer
    x = 1,284.88

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These problems maintain the same ratio (1.42) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.