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Finding the Fourth Proportional to 6.80, 9.38 and 3.89

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Solution

The fourth proportional to 6.80, 9.38 and 3.89 is: 5.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    6.80 : 9.38 = 3.89 : x
  2. Step 2: Convert to fraction form
    6.80/9.38 = 3.89/x
  3. Step 3: Cross multiply
    6.80x = 9.38 × 3.89
  4. Step 4: Simplify right side
    6.80x = 36.45
  5. Step 5: Solve for x
    x = 36.45/6.80
  6. Step 6: Final answer
    x = 5.36

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.