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Finding the Fourth Proportional to 28.14, 39.09 and 27.81

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Solution

The fourth proportional to 28.14, 39.09 and 27.81 is: 38.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    28.14 : 39.09 = 27.81 : x
  2. Step 2: Convert to fraction form
    28.14/39.09 = 27.81/x
  3. Step 3: Cross multiply
    28.14x = 39.09 × 27.81
  4. Step 4: Simplify right side
    28.14x = 1,087.09
  5. Step 5: Solve for x
    x = 1,087.09/28.14
  6. Step 6: Final answer
    x = 38.63

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.