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Finding the Third Proportional to 1.80 and 3.89

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Solution

The third proportional to 1.80 and 3.89 is: 8.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    1.80 : 3.89 = 3.89 : x
  2. Step 2: Convert to fraction form
    1.80/3.89 = 3.89/x
  3. Step 3: Cross multiply
    1.80x = 3.89 × 3.89
  4. Step 4: Simplify right side
    1.80x = 15.14
  5. Step 5: Solve for x
    x = 15.14/1.80
  6. Step 6: Final answer
    x = 8.39

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Why These Related Problems?

These problems maintain the same ratio (2.16) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.