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Finding the Third Proportional to 8.69 and 18.78

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Solution

The third proportional to 8.69 and 18.78 is: 40.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    8.69 : 18.78 = 18.78 : x
  2. Step 2: Convert to fraction form
    8.69/18.78 = 18.78/x
  3. Step 3: Cross multiply
    8.69x = 18.78 × 18.78
  4. Step 4: Simplify right side
    8.69x = 352.57
  5. Step 5: Solve for x
    x = 352.57/8.69
  6. Step 6: Final answer
    x = 40.57

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Why These Related Problems?

These problems maintain the same ratio (2.16) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.