Finding the Third Proportional to 138,405.50 and 216,834

Step by Step Solution

1. Step 1: Write the proportion equation
   138,405.50 : 216,834 = 216,834 : x
2. Step 2: Convert to fraction form
   138,405.50/216,834 = 216,834/x
3. Step 3: Cross multiply
   138,405.50x = 216,834 × 216,834
4. Step 4: Simplify right side
   138,405.50x = 47,016,983,556
5. Step 5: Solve for x
   x = 47,016,983,556/138,405.50
6. Step 6: Final answer
   x = 339,704.59