Finding the Third Proportional to 139,361.50 and 298,399.50

Step by Step Solution

1. Step 1: Write the proportion equation
   139,361.50 : 298,399.50 = 298,399.50 : x
2. Step 2: Convert to fraction form
   139,361.50/298,399.50 = 298,399.50/x
3. Step 3: Cross multiply
   139,361.50x = 298,399.50 × 298,399.50
4. Step 4: Simplify right side
   139,361.50x = 89,042,261,600.25
5. Step 5: Solve for x
   x = 89,042,261,600.25/139,361.50
6. Step 6: Final answer
   x = 638,930.13