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Finding the Fourth Proportional to 82.16, 123.13 and 81.29

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Solution

The fourth proportional to 82.16, 123.13 and 81.29 is: 121.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    82.16 : 123.13 = 81.29 : x
  2. Step 2: Convert to fraction form
    82.16/123.13 = 81.29/x
  3. Step 3: Cross multiply
    82.16x = 123.13 × 81.29
  4. Step 4: Simplify right side
    82.16x = 10,009.24
  5. Step 5: Solve for x
    x = 10,009.24/82.16
  6. Step 6: Final answer
    x = 121.83

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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.