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Finding the Fourth Proportional to 80.57, 111.19 and 68.90

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Solution

The fourth proportional to 80.57, 111.19 and 68.90 is: 95.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.57 : 111.19 = 68.90 : x
  2. Step 2: Convert to fraction form
    80.57/111.19 = 68.90/x
  3. Step 3: Cross multiply
    80.57x = 111.19 × 68.90
  4. Step 4: Simplify right side
    80.57x = 7,661.02
  5. Step 5: Solve for x
    x = 7,661.02/80.57
  6. Step 6: Final answer
    x = 95.08

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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.