Finding the Fourth Proportional to 13,179.33, 18,185.99 and 7,872.21

Step by Step Solution

1. Step 1: Write the proportion equation
   13,179.33 : 18,185.99 = 7,872.21 : x
2. Step 2: Convert to fraction form
   13,179.33/18,185.99 = 7,872.21/x
3. Step 3: Cross multiply
   13,179.33x = 18,185.99 × 7,872.21
4. Step 4: Simplify right side
   13,179.33x = 143,163,892.98
5. Step 5: Solve for x
   x = 143,163,892.98/13,179.33
6. Step 6: Final answer
   x = 10,862.76