Finding the Third Proportional to 144,940.50 and 311,308.50

Step by Step Solution

1. Step 1: Write the proportion equation
   144,940.50 : 311,308.50 = 311,308.50 : x
2. Step 2: Convert to fraction form
   144,940.50/311,308.50 = 311,308.50/x
3. Step 3: Cross multiply
   144,940.50x = 311,308.50 × 311,308.50
4. Step 4: Simplify right side
   144,940.50x = 96,912,982,172.25
5. Step 5: Solve for x
   x = 96,912,982,172.25/144,940.50
6. Step 6: Final answer
   x = 668,639.77