Finding the Fourth Proportional to 90,571.80, 134,919.15 and 89,081.40

Step by Step Solution

1. Step 1: Write the proportion equation
   90,571.80 : 134,919.15 = 89,081.40 : x
2. Step 2: Convert to fraction form
   90,571.80/134,919.15 = 89,081.40/x
3. Step 3: Cross multiply
   90,571.80x = 134,919.15 × 89,081.40
4. Step 4: Simplify right side
   90,571.80x = 12,018,786,768.81
5. Step 5: Solve for x
   x = 12,018,786,768.81/90,571.80
6. Step 6: Final answer
   x = 132,698.99