Finding the Fourth Proportional to 1,401.12, 2,099.82 and 578.55

Step by Step Solution

1. Step 1: Write the proportion equation
   1,401.12 : 2,099.82 = 578.55 : x
2. Step 2: Convert to fraction form
   1,401.12/2,099.82 = 578.55/x
3. Step 3: Cross multiply
   1,401.12x = 2,099.82 × 578.55
4. Step 4: Simplify right side
   1,401.12x = 1,214,850.86
5. Step 5: Solve for x
   x = 1,214,850.86/1,401.12
6. Step 6: Final answer
   x = 867.06