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Finding the Fourth Proportional to 121.85, 181.61 and 121.66

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Solution

The fourth proportional to 121.85, 181.61 and 121.66 is: 181.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    121.85 : 181.61 = 121.66 : x
  2. Step 2: Convert to fraction form
    121.85/181.61 = 121.66/x
  3. Step 3: Cross multiply
    121.85x = 181.61 × 121.66
  4. Step 4: Simplify right side
    121.85x = 22,095.34
  5. Step 5: Solve for x
    x = 22,095.34/121.85
  6. Step 6: Final answer
    x = 181.33

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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.