Finding the Third Proportional to 139,329 and 208,669

Step by Step Solution

1. Step 1: Write the proportion equation
   139,329 : 208,669 = 208,669 : x
2. Step 2: Convert to fraction form
   139,329/208,669 = 208,669/x
3. Step 3: Cross multiply
   139,329x = 208,669 × 208,669
4. Step 4: Simplify right side
   139,329x = 43,542,751,561
5. Step 5: Solve for x
   x = 43,542,751,561/139,329
6. Step 6: Final answer
   x = 312,517.51