Finding the Fourth Proportional to 139,438.08, 209,039.58 and 60,492.78

Step by Step Solution

1. Step 1: Write the proportion equation
   139,438.08 : 209,039.58 = 60,492.78 : x
2. Step 2: Convert to fraction form
   139,438.08/209,039.58 = 60,492.78/x
3. Step 3: Cross multiply
   139,438.08x = 209,039.58 × 60,492.78
4. Step 4: Simplify right side
   139,438.08x = 12,645,385,324.23
5. Step 5: Solve for x
   x = 12,645,385,324.23/139,438.08
6. Step 6: Final answer
   x = 90,688.18