Finding the Third Proportional to 90,639 and 196,213.50

Step by Step Solution

1. Step 1: Write the proportion equation
   90,639 : 196,213.50 = 196,213.50 : x
2. Step 2: Convert to fraction form
   90,639/196,213.50 = 196,213.50/x
3. Step 3: Cross multiply
   90,639x = 196,213.50 × 196,213.50
4. Step 4: Simplify right side
   90,639x = 38,499,737,582.25
5. Step 5: Solve for x
   x = 38,499,737,582.25/90,639
6. Step 6: Final answer
   x = 424,759.07