Finding the Fourth Proportional to 118,391.57, 163,382.78 and 64,680.07

Step by Step Solution

1. Step 1: Write the proportion equation
   118,391.57 : 163,382.78 = 64,680.07 : x
2. Step 2: Convert to fraction form
   118,391.57/163,382.78 = 64,680.07/x
3. Step 3: Cross multiply
   118,391.57x = 163,382.78 × 64,680.07
4. Step 4: Simplify right side
   118,391.57x = 10,567,608,506.88
5. Step 5: Solve for x
   x = 10,567,608,506.88/118,391.57
6. Step 6: Final answer
   x = 89,259.81