Finding the Third Proportional to 138,661.50 and 213,867

Step by Step Solution

1. Step 1: Write the proportion equation
   138,661.50 : 213,867 = 213,867 : x
2. Step 2: Convert to fraction form
   138,661.50/213,867 = 213,867/x
3. Step 3: Cross multiply
   138,661.50x = 213,867 × 213,867
4. Step 4: Simplify right side
   138,661.50x = 45,739,093,689
5. Step 5: Solve for x
   x = 45,739,093,689/138,661.50
6. Step 6: Final answer
   x = 329,861.52