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Finding the Third Proportional to 75.75 and 78.75

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Solution

The third proportional to 75.75 and 78.75 is: 81.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    75.75 : 78.75 = 78.75 : x
  2. Step 2: Convert to fraction form
    75.75/78.75 = 78.75/x
  3. Step 3: Cross multiply
    75.75x = 78.75 × 78.75
  4. Step 4: Simplify right side
    75.75x = 6,201.56
  5. Step 5: Solve for x
    x = 6,201.56/75.75
  6. Step 6: Final answer
    x = 81.87

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Why These Related Problems?

These problems maintain the same ratio (1.04) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.