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Finding the Third Proportional to 2.87 and 5.11

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Solution

The third proportional to 2.87 and 5.11 is: 9.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    2.87 : 5.11 = 5.11 : x
  2. Step 2: Convert to fraction form
    2.87/5.11 = 5.11/x
  3. Step 3: Cross multiply
    2.87x = 5.11 × 5.11
  4. Step 4: Simplify right side
    2.87x = 26.10
  5. Step 5: Solve for x
    x = 26.10/2.87
  6. Step 6: Final answer
    x = 9.10

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Why These Related Problems?

These problems maintain the same ratio (1.78) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.