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Finding the Third Proportional to 3.19 and 8.20

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Solution

The third proportional to 3.19 and 8.20 is: 21.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    3.19 : 8.20 = 8.20 : x
  2. Step 2: Convert to fraction form
    3.19/8.20 = 8.20/x
  3. Step 3: Cross multiply
    3.19x = 8.20 × 8.20
  4. Step 4: Simplify right side
    3.19x = 67.32
  5. Step 5: Solve for x
    x = 67.32/3.19
  6. Step 6: Final answer
    x = 21.07

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Why These Related Problems?

These problems maintain the same ratio (2.57) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.