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Finding the Fourth Proportional to 80.60, 111.20 and 68.30

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Solution

The fourth proportional to 80.60, 111.20 and 68.30 is: 94.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.60 : 111.20 = 68.30 : x
  2. Step 2: Convert to fraction form
    80.60/111.20 = 68.30/x
  3. Step 3: Cross multiply
    80.60x = 111.20 × 68.30
  4. Step 4: Simplify right side
    80.60x = 7,594.96
  5. Step 5: Solve for x
    x = 7,594.96/80.60
  6. Step 6: Final answer
    x = 94.23

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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.