Finding the Third Proportional to 18.30 and 38.71

Step by Step Solution

1. Step 1: Write the proportion equation
   18.30 : 38.71 = 38.71 : x
2. Step 2: Convert to fraction form
   18.30/38.71 = 38.71/x
3. Step 3: Cross multiply
   18.30x = 38.71 × 38.71
4. Step 4: Simplify right side
   18.30x = 1,498.39
5. Step 5: Solve for x
   x = 1,498.39/18.30
6. Step 6: Final answer
   x = 81.88