Finding the Third Proportional to 772.88 and 828.56

Step by Step Solution

1. Step 1: Write the proportion equation
   772.88 : 828.56 = 828.56 : x
2. Step 2: Convert to fraction form
   772.88/828.56 = 828.56/x
3. Step 3: Cross multiply
   772.88x = 828.56 × 828.56
4. Step 4: Simplify right side
   772.88x = 686,515.82
5. Step 5: Solve for x
   x = 686,515.82/772.88
6. Step 6: Final answer
   x = 888.26