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Finding the Fourth Proportional to 83.39, 125.78 and 80.55

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Solution

The fourth proportional to 83.39, 125.78 and 80.55 is: 121.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    83.39 : 125.78 = 80.55 : x
  2. Step 2: Convert to fraction form
    83.39/125.78 = 80.55/x
  3. Step 3: Cross multiply
    83.39x = 125.78 × 80.55
  4. Step 4: Simplify right side
    83.39x = 10,131.18
  5. Step 5: Solve for x
    x = 10,131.18/83.39
  6. Step 6: Final answer
    x = 121.50

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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.