Finding the Third Proportional to 90,639 and 213,313.50

Step by Step Solution

1. Step 1: Write the proportion equation
   90,639 : 213,313.50 = 213,313.50 : x
2. Step 2: Convert to fraction form
   90,639/213,313.50 = 213,313.50/x
3. Step 3: Cross multiply
   90,639x = 213,313.50 × 213,313.50
4. Step 4: Simplify right side
   90,639x = 45,502,649,282.25
5. Step 5: Solve for x
   x = 45,502,649,282.25/90,639
6. Step 6: Final answer
   x = 502,020.65