Finding the Fourth Proportional to 103,680.35, 155,684.55 and 78,748.55

Step by Step Solution

1. Step 1: Write the proportion equation
   103,680.35 : 155,684.55 = 78,748.55 : x
2. Step 2: Convert to fraction form
   103,680.35/155,684.55 = 78,748.55/x
3. Step 3: Cross multiply
   103,680.35x = 155,684.55 × 78,748.55
4. Step 4: Simplify right side
   103,680.35x = 12,259,932,569.90
5. Step 5: Solve for x
   x = 12,259,932,569.90/103,680.35
6. Step 6: Final answer
   x = 118,247.41