Finding the Third Proportional to 18.82 and 39.72

Step by Step Solution

1. Step 1: Write the proportion equation
   18.82 : 39.72 = 39.72 : x
2. Step 2: Convert to fraction form
   18.82/39.72 = 39.72/x
3. Step 3: Cross multiply
   18.82x = 39.72 × 39.72
4. Step 4: Simplify right side
   18.82x = 1,577.85
5. Step 5: Solve for x
   x = 1,577.85/18.82
6. Step 6: Final answer
   x = 83.86