Finding the Fourth Proportional to 88,931.30, 133,068.90 and 81,058.10

Step by Step Solution

1. Step 1: Write the proportion equation
   88,931.30 : 133,068.90 = 81,058.10 : x
2. Step 2: Convert to fraction form
   88,931.30/133,068.90 = 81,058.10/x
3. Step 3: Cross multiply
   88,931.30x = 133,068.90 × 81,058.10
4. Step 4: Simplify right side
   88,931.30x = 10,786,312,203.09
5. Step 5: Solve for x
   x = 10,786,312,203.09/88,931.30
6. Step 6: Final answer
   x = 121,288.14