Finding the Third Proportional to 128,910 and 199,198.50

Step by Step Solution

1. Step 1: Write the proportion equation
   128,910 : 199,198.50 = 199,198.50 : x
2. Step 2: Convert to fraction form
   128,910/199,198.50 = 199,198.50/x
3. Step 3: Cross multiply
   128,910x = 199,198.50 × 199,198.50
4. Step 4: Simplify right side
   128,910x = 39,680,042,402.25
5. Step 5: Solve for x
   x = 39,680,042,402.25/128,910
6. Step 6: Final answer
   x = 307,811.98