Finding the Third Proportional to 778.88 and 1,002.56

Step by Step Solution

1. Step 1: Write the proportion equation
   778.88 : 1,002.56 = 1,002.56 : x
2. Step 2: Convert to fraction form
   778.88/1,002.56 = 1,002.56/x
3. Step 3: Cross multiply
   778.88x = 1,002.56 × 1,002.56
4. Step 4: Simplify right side
   778.88x = 1,005,131.57
5. Step 5: Solve for x
   x = 1,005,131.57/778.88
6. Step 6: Final answer
   x = 1,290.49