Finding the Third Proportional to 139,111.75 and 208,697.75

Step by Step Solution

1. Step 1: Write the proportion equation
   139,111.75 : 208,697.75 = 208,697.75 : x
2. Step 2: Convert to fraction form
   139,111.75/208,697.75 = 208,697.75/x
3. Step 3: Cross multiply
   139,111.75x = 208,697.75 × 208,697.75
4. Step 4: Simplify right side
   139,111.75x = 43,554,750,855.06
5. Step 5: Solve for x
   x = 43,554,750,855.06/139,111.75
6. Step 6: Final answer
   x = 313,091.82