Finding the Third Proportional to 9,687.94 and 19,786.78

Step by Step Solution

1. Step 1: Write the proportion equation
   9,687.94 : 19,786.78 = 19,786.78 : x
2. Step 2: Convert to fraction form
   9,687.94/19,786.78 = 19,786.78/x
3. Step 3: Cross multiply
   9,687.94x = 19,786.78 × 19,786.78
4. Step 4: Simplify right side
   9,687.94x = 391,516,712.24
5. Step 5: Solve for x
   x = 391,516,712.24/9,687.94
6. Step 6: Final answer
   x = 40,412.80