Finding the Third Proportional to 140,976 and 309,990

Step by Step Solution

1. Step 1: Write the proportion equation
   140,976 : 309,990 = 309,990 : x
2. Step 2: Convert to fraction form
   140,976/309,990 = 309,990/x
3. Step 3: Cross multiply
   140,976x = 309,990 × 309,990
4. Step 4: Simplify right side
   140,976x = 96,093,800,100
5. Step 5: Solve for x
   x = 96,093,800,100/140,976
6. Step 6: Final answer
   x = 681,632.34