Finding the Fourth Proportional to 8,111.84, 12,168.36 and 7,144.64

Step by Step Solution

1. Step 1: Write the proportion equation
   8,111.84 : 12,168.36 = 7,144.64 : x
2. Step 2: Convert to fraction form
   8,111.84/12,168.36 = 7,144.64/x
3. Step 3: Cross multiply
   8,111.84x = 12,168.36 × 7,144.64
4. Step 4: Simplify right side
   8,111.84x = 86,938,551.59
5. Step 5: Solve for x
   x = 86,938,551.59/8,111.84
6. Step 6: Final answer
   x = 10,717.49