Finding the Fourth Proportional to 13,091.72, 18,066.42 and 8,621.96

Step by Step Solution

1. Step 1: Write the proportion equation
   13,091.72 : 18,066.42 = 8,621.96 : x
2. Step 2: Convert to fraction form
   13,091.72/18,066.42 = 8,621.96/x
3. Step 3: Cross multiply
   13,091.72x = 18,066.42 × 8,621.96
4. Step 4: Simplify right side
   13,091.72x = 155,767,950.58
5. Step 5: Solve for x
   x = 155,767,950.58/13,091.72
6. Step 6: Final answer
   x = 11,898.20