Finding the Third Proportional to 108,660 and 172,890

Step by Step Solution

1. Step 1: Write the proportion equation
   108,660 : 172,890 = 172,890 : x
2. Step 2: Convert to fraction form
   108,660/172,890 = 172,890/x
3. Step 3: Cross multiply
   108,660x = 172,890 × 172,890
4. Step 4: Simplify right side
   108,660x = 29,890,952,100
5. Step 5: Solve for x
   x = 29,890,952,100/108,660
6. Step 6: Final answer
   x = 275,086.99