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Finding the Fourth Proportional to 82.14, 123.82 and 80.30

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Solution

The fourth proportional to 82.14, 123.82 and 80.30 is: 121.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    82.14 : 123.82 = 80.30 : x
  2. Step 2: Convert to fraction form
    82.14/123.82 = 80.30/x
  3. Step 3: Cross multiply
    82.14x = 123.82 × 80.30
  4. Step 4: Simplify right side
    82.14x = 9,942.34
  5. Step 5: Solve for x
    x = 9,942.34/82.14
  6. Step 6: Final answer
    x = 121.04

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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.