Finding the Third Proportional to 99,990 and 140,629.50

Step by Step Solution

1. Step 1: Write the proportion equation
   99,990 : 140,629.50 = 140,629.50 : x
2. Step 2: Convert to fraction form
   99,990/140,629.50 = 140,629.50/x
3. Step 3: Cross multiply
   99,990x = 140,629.50 × 140,629.50
4. Step 4: Simplify right side
   99,990x = 19,776,656,270.25
5. Step 5: Solve for x
   x = 19,776,656,270.25/99,990
6. Step 6: Final answer
   x = 197,786.34