Finding the Fourth Proportional to 128,858.10, 193,287.15 and 89,492.10

Step by Step Solution

1. Step 1: Write the proportion equation
   128,858.10 : 193,287.15 = 89,492.10 : x
2. Step 2: Convert to fraction form
   128,858.10/193,287.15 = 89,492.10/x
3. Step 3: Cross multiply
   128,858.10x = 193,287.15 × 89,492.10
4. Step 4: Simplify right side
   128,858.10x = 17,297,672,956.52
5. Step 5: Solve for x
   x = 17,297,672,956.52/128,858.10
6. Step 6: Final answer
   x = 134,238.15