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Finding the Third Proportional to 3.80 and 8.30

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Solution

The third proportional to 3.80 and 8.30 is: 18.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    3.80 : 8.30 = 8.30 : x
  2. Step 2: Convert to fraction form
    3.80/8.30 = 8.30/x
  3. Step 3: Cross multiply
    3.80x = 8.30 × 8.30
  4. Step 4: Simplify right side
    3.80x = 68.84
  5. Step 5: Solve for x
    x = 68.84/3.80
  6. Step 6: Final answer
    x = 18.13

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Why These Related Problems?

These problems maintain the same ratio (2.19) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.