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Finding the Third Proportional to 57 and 87

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Solution

The third proportional to 57 and 87 is: 132.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    57 : 87 = 87 : x
  2. Step 2: Convert to fraction form
    57/87 = 87/x
  3. Step 3: Cross multiply
    57x = 87 × 87
  4. Step 4: Simplify right side
    57x = 7,569
  5. Step 5: Solve for x
    x = 7,569/57
  6. Step 6: Final answer
    x = 132.79

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Why These Related Problems?

These problems maintain the same ratio (1.53) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.