Finding the Fourth Proportional to 2,800.76, 4,200.16 and 825.86

Step by Step Solution

1. Step 1: Write the proportion equation
   2,800.76 : 4,200.16 = 825.86 : x
2. Step 2: Convert to fraction form
   2,800.76/4,200.16 = 825.86/x
3. Step 3: Cross multiply
   2,800.76x = 4,200.16 × 825.86
4. Step 4: Simplify right side
   2,800.76x = 3,468,757.29
5. Step 5: Solve for x
   x = 3,468,757.29/2,800.76
6. Step 6: Final answer
   x = 1,238.51