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Finding the Fourth Proportional to 121.05, 181.61 and 82.17

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Solution

The fourth proportional to 121.05, 181.61 and 82.17 is: 123.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    121.05 : 181.61 = 82.17 : x
  2. Step 2: Convert to fraction form
    121.05/181.61 = 82.17/x
  3. Step 3: Cross multiply
    121.05x = 181.61 × 82.17
  4. Step 4: Simplify right side
    121.05x = 14,922.89
  5. Step 5: Solve for x
    x = 14,922.89/121.05
  6. Step 6: Final answer
    x = 123.28

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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.