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Finding the Fourth Proportional to 121.80, 181.82 and 104.79

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Solution

The fourth proportional to 121.80, 181.82 and 104.79 is: 156.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    121.80 : 181.82 = 104.79 : x
  2. Step 2: Convert to fraction form
    121.80/181.82 = 104.79/x
  3. Step 3: Cross multiply
    121.80x = 181.82 × 104.79
  4. Step 4: Simplify right side
    121.80x = 19,052.92
  5. Step 5: Solve for x
    x = 19,052.92/121.80
  6. Step 6: Final answer
    x = 156.43

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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.