Finding the Fourth Proportional to 8,115.78, 12,157.89 and 5,334.08

Step by Step Solution

1. Step 1: Write the proportion equation
   8,115.78 : 12,157.89 = 5,334.08 : x
2. Step 2: Convert to fraction form
   8,115.78/12,157.89 = 5,334.08/x
3. Step 3: Cross multiply
   8,115.78x = 12,157.89 × 5,334.08
4. Step 4: Simplify right side
   8,115.78x = 64,851,097.10
5. Step 5: Solve for x
   x = 64,851,097.10/8,115.78
6. Step 6: Final answer
   x = 7,990.74