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Finding the Fourth Proportional to 80.53, 121.39 and 67.09

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Solution

The fourth proportional to 80.53, 121.39 and 67.09 is: 101.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.53 : 121.39 = 67.09 : x
  2. Step 2: Convert to fraction form
    80.53/121.39 = 67.09/x
  3. Step 3: Cross multiply
    80.53x = 121.39 × 67.09
  4. Step 4: Simplify right side
    80.53x = 8,143.72
  5. Step 5: Solve for x
    x = 8,143.72/80.53
  6. Step 6: Final answer
    x = 101.13

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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.