Finding the Third Proportional to 138,423 and 213,757.50

Step by Step Solution

1. Step 1: Write the proportion equation
   138,423 : 213,757.50 = 213,757.50 : x
2. Step 2: Convert to fraction form
   138,423/213,757.50 = 213,757.50/x
3. Step 3: Cross multiply
   138,423x = 213,757.50 × 213,757.50
4. Step 4: Simplify right side
   138,423x = 45,692,268,806.25
5. Step 5: Solve for x
   x = 45,692,268,806.25/138,423
6. Step 6: Final answer
   x = 330,091.59