Finding the Third Proportional to 276.56 and 442.78

Step by Step Solution

1. Step 1: Write the proportion equation
   276.56 : 442.78 = 442.78 : x
2. Step 2: Convert to fraction form
   276.56/442.78 = 442.78/x
3. Step 3: Cross multiply
   276.56x = 442.78 × 442.78
4. Step 4: Simplify right side
   276.56x = 196,055.24
5. Step 5: Solve for x
   x = 196,055.24/276.56
6. Step 6: Final answer
   x = 708.90