Finding the Third Proportional to 777.94 and 2,020.78

Step by Step Solution

1. Step 1: Write the proportion equation
   777.94 : 2,020.78 = 2,020.78 : x
2. Step 2: Convert to fraction form
   777.94/2,020.78 = 2,020.78/x
3. Step 3: Cross multiply
   777.94x = 2,020.78 × 2,020.78
4. Step 4: Simplify right side
   777.94x = 4,083,556.86
5. Step 5: Solve for x
   x = 4,083,556.86/777.94
6. Step 6: Final answer
   x = 5,249.21