Finding the Third Proportional to 144,145.50 and 315,441

Step by Step Solution

1. Step 1: Write the proportion equation
   144,145.50 : 315,441 = 315,441 : x
2. Step 2: Convert to fraction form
   144,145.50/315,441 = 315,441/x
3. Step 3: Cross multiply
   144,145.50x = 315,441 × 315,441
4. Step 4: Simplify right side
   144,145.50x = 99,503,024,481
5. Step 5: Solve for x
   x = 99,503,024,481/144,145.50
6. Step 6: Final answer
   x = 690,295.74