Finding the Third Proportional to 622.78 and 919.78

Step by Step Solution

1. Step 1: Write the proportion equation
   622.78 : 919.78 = 919.78 : x
2. Step 2: Convert to fraction form
   622.78/919.78 = 919.78/x
3. Step 3: Cross multiply
   622.78x = 919.78 × 919.78
4. Step 4: Simplify right side
   622.78x = 845,997.55
5. Step 5: Solve for x
   x = 845,997.55/622.78
6. Step 6: Final answer
   x = 1,358.42