Finding the Fourth Proportional to 8,111.42, 12,161.49 and 3,181.55

Step by Step Solution

1. Step 1: Write the proportion equation
   8,111.42 : 12,161.49 = 3,181.55 : x
2. Step 2: Convert to fraction form
   8,111.42/12,161.49 = 3,181.55/x
3. Step 3: Cross multiply
   8,111.42x = 12,161.49 × 3,181.55
4. Step 4: Simplify right side
   8,111.42x = 38,692,388.51
5. Step 5: Solve for x
   x = 38,692,388.51/8,111.42
6. Step 6: Final answer
   x = 4,770.12