Finding the Fourth Proportional to 2,112.56, 3,168.17 and 879.65

Step by Step Solution

1. Step 1: Write the proportion equation
   2,112.56 : 3,168.17 = 879.65 : x
2. Step 2: Convert to fraction form
   2,112.56/3,168.17 = 879.65/x
3. Step 3: Cross multiply
   2,112.56x = 3,168.17 × 879.65
4. Step 4: Simplify right side
   2,112.56x = 2,786,880.74
5. Step 5: Solve for x
   x = 2,786,880.74/2,112.56
6. Step 6: Final answer
   x = 1,319.20