Finding the Third Proportional to 90,610.50 and 213,208.50

Step by Step Solution

1. Step 1: Write the proportion equation
   90,610.50 : 213,208.50 = 213,208.50 : x
2. Step 2: Convert to fraction form
   90,610.50/213,208.50 = 213,208.50/x
3. Step 3: Cross multiply
   90,610.50x = 213,208.50 × 213,208.50
4. Step 4: Simplify right side
   90,610.50x = 45,457,864,472.25
5. Step 5: Solve for x
   x = 45,457,864,472.25/90,610.50
6. Step 6: Final answer
   x = 501,684.29