Finding the Third Proportional to 128,401.50 and 192,991.50

Step by Step Solution

1. Step 1: Write the proportion equation
   128,401.50 : 192,991.50 = 192,991.50 : x
2. Step 2: Convert to fraction form
   128,401.50/192,991.50 = 192,991.50/x
3. Step 3: Cross multiply
   128,401.50x = 192,991.50 × 192,991.50
4. Step 4: Simplify right side
   128,401.50x = 37,245,719,072.25
5. Step 5: Solve for x
   x = 37,245,719,072.25/128,401.50
6. Step 6: Final answer
   x = 290,072.31