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Finding the Fourth Proportional to 80.80, 111.27 and 69.10

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Solution

The fourth proportional to 80.80, 111.27 and 69.10 is: 95.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.80 : 111.27 = 69.10 : x
  2. Step 2: Convert to fraction form
    80.80/111.27 = 69.10/x
  3. Step 3: Cross multiply
    80.80x = 111.27 × 69.10
  4. Step 4: Simplify right side
    80.80x = 7,688.76
  5. Step 5: Solve for x
    x = 7,688.76/80.80
  6. Step 6: Final answer
    x = 95.16

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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.