Finding the Third Proportional to 11.81 and 18.31

Step by Step Solution

1. Step 1: Write the proportion equation
   11.81 : 18.31 = 18.31 : x
2. Step 2: Convert to fraction form
   11.81/18.31 = 18.31/x
3. Step 3: Cross multiply
   11.81x = 18.31 × 18.31
4. Step 4: Simplify right side
   11.81x = 335.35
5. Step 5: Solve for x
   x = 335.35/11.81
6. Step 6: Final answer
   x = 28.39