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Finding the Fourth Proportional to 69.40, 104.07 and 20.64

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Solution

The fourth proportional to 69.40, 104.07 and 20.64 is: 30.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    69.40 : 104.07 = 20.64 : x
  2. Step 2: Convert to fraction form
    69.40/104.07 = 20.64/x
  3. Step 3: Cross multiply
    69.40x = 104.07 × 20.64
  4. Step 4: Simplify right side
    69.40x = 2,148.00
  5. Step 5: Solve for x
    x = 2,148.00/69.40
  6. Step 6: Final answer
    x = 30.95

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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.