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Finding the Fourth Proportional to 80.12, 119.63 and 69.28

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Solution

The fourth proportional to 80.12, 119.63 and 69.28 is: 103.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.12 : 119.63 = 69.28 : x
  2. Step 2: Convert to fraction form
    80.12/119.63 = 69.28/x
  3. Step 3: Cross multiply
    80.12x = 119.63 × 69.28
  4. Step 4: Simplify right side
    80.12x = 8,287.84
  5. Step 5: Solve for x
    x = 8,287.84/80.12
  6. Step 6: Final answer
    x = 103.44

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.