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Finding the Fourth Proportional to 80.38, 121.18 and 79.30

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Solution

The fourth proportional to 80.38, 121.18 and 79.30 is: 119.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.38 : 121.18 = 79.30 : x
  2. Step 2: Convert to fraction form
    80.38/121.18 = 79.30/x
  3. Step 3: Cross multiply
    80.38x = 121.18 × 79.30
  4. Step 4: Simplify right side
    80.38x = 9,609.57
  5. Step 5: Solve for x
    x = 9,609.57/80.38
  6. Step 6: Final answer
    x = 119.55

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.