Finding the Third Proportional to 90,617.50 and 213,205.50

Step by Step Solution

1. Step 1: Write the proportion equation
   90,617.50 : 213,205.50 = 213,205.50 : x
2. Step 2: Convert to fraction form
   90,617.50/213,205.50 = 213,205.50/x
3. Step 3: Cross multiply
   90,617.50x = 213,205.50 × 213,205.50
4. Step 4: Simplify right side
   90,617.50x = 45,456,585,230.25
5. Step 5: Solve for x
   x = 45,456,585,230.25/90,617.50
6. Step 6: Final answer
   x = 501,631.42