Finding the Fourth Proportional to 2,112.72, 3,166.24 and 878.70

Step by Step Solution

1. Step 1: Write the proportion equation
   2,112.72 : 3,166.24 = 878.70 : x
2. Step 2: Convert to fraction form
   2,112.72/3,166.24 = 878.70/x
3. Step 3: Cross multiply
   2,112.72x = 3,166.24 × 878.70
4. Step 4: Simplify right side
   2,112.72x = 2,782,175.09
5. Step 5: Solve for x
   x = 2,782,175.09/2,112.72
6. Step 6: Final answer
   x = 1,316.87