Finding the Fourth Proportional to 139,578.39, 192,649.18 and 85,142.59

Step by Step Solution

1. Step 1: Write the proportion equation
   139,578.39 : 192,649.18 = 85,142.59 : x
2. Step 2: Convert to fraction form
   139,578.39/192,649.18 = 85,142.59/x
3. Step 3: Cross multiply
   139,578.39x = 192,649.18 × 85,142.59
4. Step 4: Simplify right side
   139,578.39x = 16,402,649,452.10
5. Step 5: Solve for x
   x = 16,402,649,452.10/139,578.39
6. Step 6: Final answer
   x = 117,515.68