Finding the Third Proportional to 138,108 and 209,029.50

Step by Step Solution

1. Step 1: Write the proportion equation
   138,108 : 209,029.50 = 209,029.50 : x
2. Step 2: Convert to fraction form
   138,108/209,029.50 = 209,029.50/x
3. Step 3: Cross multiply
   138,108x = 209,029.50 × 209,029.50
4. Step 4: Simplify right side
   138,108x = 43,693,331,870.25
5. Step 5: Solve for x
   x = 43,693,331,870.25/138,108
6. Step 6: Final answer
   x = 316,370.75