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Finding the Fourth Proportional to 69.09, 103.55 and 38.64

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Solution

The fourth proportional to 69.09, 103.55 and 38.64 is: 57.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    69.09 : 103.55 = 38.64 : x
  2. Step 2: Convert to fraction form
    69.09/103.55 = 38.64/x
  3. Step 3: Cross multiply
    69.09x = 103.55 × 38.64
  4. Step 4: Simplify right side
    69.09x = 4,001.17
  5. Step 5: Solve for x
    x = 4,001.17/69.09
  6. Step 6: Final answer
    x = 57.91

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.