Finding the Third Proportional to 20.78 and 31.83

Step by Step Solution

1. Step 1: Write the proportion equation
   20.78 : 31.83 = 31.83 : x
2. Step 2: Convert to fraction form
   20.78/31.83 = 31.83/x
3. Step 3: Cross multiply
   20.78x = 31.83 × 31.83
4. Step 4: Simplify right side
   20.78x = 1,013.03
5. Step 5: Solve for x
   x = 1,013.03/20.78
6. Step 6: Final answer
   x = 48.75