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Finding the Fourth Proportional to 83.85, 125.85 and 72.51

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Solution

The fourth proportional to 83.85, 125.85 and 72.51 is: 108.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    83.85 : 125.85 = 72.51 : x
  2. Step 2: Convert to fraction form
    83.85/125.85 = 72.51/x
  3. Step 3: Cross multiply
    83.85x = 125.85 × 72.51
  4. Step 4: Simplify right side
    83.85x = 9,125.38
  5. Step 5: Solve for x
    x = 9,125.38/83.85
  6. Step 6: Final answer
    x = 108.83

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.