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Finding the Third Proportional to 77.50 and 87.50

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Solution

The third proportional to 77.50 and 87.50 is: 98.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.50 : 87.50 = 87.50 : x
  2. Step 2: Convert to fraction form
    77.50/87.50 = 87.50/x
  3. Step 3: Cross multiply
    77.50x = 87.50 × 87.50
  4. Step 4: Simplify right side
    77.50x = 7,656.25
  5. Step 5: Solve for x
    x = 7,656.25/77.50
  6. Step 6: Final answer
    x = 98.79

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Why These Related Problems?

These problems maintain the same ratio (1.13) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.