Finding the Third Proportional to 111,171 and 172,399.50

Step by Step Solution

1. Step 1: Write the proportion equation
   111,171 : 172,399.50 = 172,399.50 : x
2. Step 2: Convert to fraction form
   111,171/172,399.50 = 172,399.50/x
3. Step 3: Cross multiply
   111,171x = 172,399.50 × 172,399.50
4. Step 4: Simplify right side
   111,171x = 29,721,587,600.25
5. Step 5: Solve for x
   x = 29,721,587,600.25/111,171
6. Step 6: Final answer
   x = 267,350.19