Finding the Third Proportional to 21.94 and 42.19

Step by Step Solution

1. Step 1: Write the proportion equation
   21.94 : 42.19 = 42.19 : x
2. Step 2: Convert to fraction form
   21.94/42.19 = 42.19/x
3. Step 3: Cross multiply
   21.94x = 42.19 × 42.19
4. Step 4: Simplify right side
   21.94x = 1,779.79
5. Step 5: Solve for x
   x = 1,779.79/21.94
6. Step 6: Final answer
   x = 81.13