Finding the Fourth Proportional to 139,878.28, 209,607.90 and 60,949.72

Step by Step Solution

1. Step 1: Write the proportion equation
   139,878.28 : 209,607.90 = 60,949.72 : x
2. Step 2: Convert to fraction form
   139,878.28/209,607.90 = 60,949.72/x
3. Step 3: Cross multiply
   139,878.28x = 209,607.90 × 60,949.72
4. Step 4: Simplify right side
   139,878.28x = 12,775,542,814.79
5. Step 5: Solve for x
   x = 12,775,542,814.79/139,878.28
6. Step 6: Final answer
   x = 91,333.29