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Finding the Third Proportional to 3.20 and 5.10

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Solution

The third proportional to 3.20 and 5.10 is: 8.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    3.20 : 5.10 = 5.10 : x
  2. Step 2: Convert to fraction form
    3.20/5.10 = 5.10/x
  3. Step 3: Cross multiply
    3.20x = 5.10 × 5.10
  4. Step 4: Simplify right side
    3.20x = 26.01
  5. Step 5: Solve for x
    x = 26.01/3.20
  6. Step 6: Final answer
    x = 8.13

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Why These Related Problems?

These problems maintain the same ratio (1.59) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.