Finding the Third Proportional to 90,639 and 140,697

Step by Step Solution

1. Step 1: Write the proportion equation
   90,639 : 140,697 = 140,697 : x
2. Step 2: Convert to fraction form
   90,639/140,697 = 140,697/x
3. Step 3: Cross multiply
   90,639x = 140,697 × 140,697
4. Step 4: Simplify right side
   90,639x = 19,795,645,809
5. Step 5: Solve for x
   x = 19,795,645,809/90,639
6. Step 6: Final answer
   x = 218,400.97