Finding the Third Proportional to 9,421.31 and 19,811.81

Step by Step Solution

1. Step 1: Write the proportion equation
   9,421.31 : 19,811.81 = 19,811.81 : x
2. Step 2: Convert to fraction form
   9,421.31/19,811.81 = 19,811.81/x
3. Step 3: Cross multiply
   9,421.31x = 19,811.81 × 19,811.81
4. Step 4: Simplify right side
   9,421.31x = 392,507,914.54
5. Step 5: Solve for x
   x = 392,507,914.54/9,421.31
6. Step 6: Final answer
   x = 41,661.70