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Finding the Third Proportional to 69 and 77.25

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Solution

The third proportional to 69 and 77.25 is: 86.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    69 : 77.25 = 77.25 : x
  2. Step 2: Convert to fraction form
    69/77.25 = 77.25/x
  3. Step 3: Cross multiply
    69x = 77.25 × 77.25
  4. Step 4: Simplify right side
    69x = 5,967.56
  5. Step 5: Solve for x
    x = 5,967.56/69
  6. Step 6: Final answer
    x = 86.49

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Why These Related Problems?

These problems maintain the same ratio (1.12) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.