Finding the Third Proportional to 128,196 and 199,015.31

Step by Step Solution

1. Step 1: Write the proportion equation
   128,196 : 199,015.31 = 199,015.31 : x
2. Step 2: Convert to fraction form
   128,196/199,015.31 = 199,015.31/x
3. Step 3: Cross multiply
   128,196x = 199,015.31 × 199,015.31
4. Step 4: Simplify right side
   128,196x = 39,607,094,609.47
5. Step 5: Solve for x
   x = 39,607,094,609.47/128,196
6. Step 6: Final answer
   x = 308,957.34