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Finding the Fourth Proportional to 85.82, 127.90 and 82.43

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Solution

The fourth proportional to 85.82, 127.90 and 82.43 is: 122.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.82 : 127.90 = 82.43 : x
  2. Step 2: Convert to fraction form
    85.82/127.90 = 82.43/x
  3. Step 3: Cross multiply
    85.82x = 127.90 × 82.43
  4. Step 4: Simplify right side
    85.82x = 10,542.80
  5. Step 5: Solve for x
    x = 10,542.80/85.82
  6. Step 6: Final answer
    x = 122.85

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.