Finding the Third Proportional to 128,186 and 198,998.50

Step by Step Solution

1. Step 1: Write the proportion equation
   128,186 : 198,998.50 = 198,998.50 : x
2. Step 2: Convert to fraction form
   128,186/198,998.50 = 198,998.50/x
3. Step 3: Cross multiply
   128,186x = 198,998.50 × 198,998.50
4. Step 4: Simplify right side
   128,186x = 39,600,403,002.25
5. Step 5: Solve for x
   x = 39,600,403,002.25/128,186
6. Step 6: Final answer
   x = 308,929.24