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Finding the Third Proportional to 3.09 and 5.20

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Solution

The third proportional to 3.09 and 5.20 is: 8.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    3.09 : 5.20 = 5.20 : x
  2. Step 2: Convert to fraction form
    3.09/5.20 = 5.20/x
  3. Step 3: Cross multiply
    3.09x = 5.20 × 5.20
  4. Step 4: Simplify right side
    3.09x = 27.07
  5. Step 5: Solve for x
    x = 27.07/3.09
  6. Step 6: Final answer
    x = 8.75

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Why These Related Problems?

These problems maintain the same ratio (1.68) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.