Finding the Fourth Proportional to 1,015.79, 1,401.89 and 622.58

Step by Step Solution

1. Step 1: Write the proportion equation
   1,015.79 : 1,401.89 = 622.58 : x
2. Step 2: Convert to fraction form
   1,015.79/1,401.89 = 622.58/x
3. Step 3: Cross multiply
   1,015.79x = 1,401.89 × 622.58
4. Step 4: Simplify right side
   1,015.79x = 872,778.55
5. Step 5: Solve for x
   x = 872,778.55/1,015.79
6. Step 6: Final answer
   x = 859.22