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Finding the Fourth Proportional to 5.66, 7.81 and 3.85

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Solution

The fourth proportional to 5.66, 7.81 and 3.85 is: 5.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    5.66 : 7.81 = 3.85 : x
  2. Step 2: Convert to fraction form
    5.66/7.81 = 3.85/x
  3. Step 3: Cross multiply
    5.66x = 7.81 × 3.85
  4. Step 4: Simplify right side
    5.66x = 30.04
  5. Step 5: Solve for x
    x = 30.04/5.66
  6. Step 6: Final answer
    x = 5.31

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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.