Finding the Third Proportional to 419.55 and 622.69

Step by Step Solution

1. Step 1: Write the proportion equation
   419.55 : 622.69 = 622.69 : x
2. Step 2: Convert to fraction form
   419.55/622.69 = 622.69/x
3. Step 3: Cross multiply
   419.55x = 622.69 × 622.69
4. Step 4: Simplify right side
   419.55x = 387,739.72
5. Step 5: Solve for x
   x = 387,739.72/419.55
6. Step 6: Final answer
   x = 924.17