Finding the Fourth Proportional to 2,801.10, 4,200.90 and 852.78

Step by Step Solution

1. Step 1: Write the proportion equation
   2,801.10 : 4,200.90 = 852.78 : x
2. Step 2: Convert to fraction form
   2,801.10/4,200.90 = 852.78/x
3. Step 3: Cross multiply
   2,801.10x = 4,200.90 × 852.78
4. Step 4: Simplify right side
   2,801.10x = 3,582,443.50
5. Step 5: Solve for x
   x = 3,582,443.50/2,801.10
6. Step 6: Final answer
   x = 1,278.94