Finding the Fourth Proportional to 2,112.87, 3,168.35 and 879.55

Step by Step Solution

1. Step 1: Write the proportion equation
   2,112.87 : 3,168.35 = 879.55 : x
2. Step 2: Convert to fraction form
   2,112.87/3,168.35 = 879.55/x
3. Step 3: Cross multiply
   2,112.87x = 3,168.35 × 879.55
4. Step 4: Simplify right side
   2,112.87x = 2,786,713.22
5. Step 5: Solve for x
   x = 2,786,713.22/2,112.87
6. Step 6: Final answer
   x = 1,318.92