Finding the Third Proportional to 139,360.50 and 309,325.50

Step by Step Solution

1. Step 1: Write the proportion equation
   139,360.50 : 309,325.50 = 309,325.50 : x
2. Step 2: Convert to fraction form
   139,360.50/309,325.50 = 309,325.50/x
3. Step 3: Cross multiply
   139,360.50x = 309,325.50 × 309,325.50
4. Step 4: Simplify right side
   139,360.50x = 95,682,264,950.25
5. Step 5: Solve for x
   x = 95,682,264,950.25/139,360.50
6. Step 6: Final answer
   x = 686,580.95