Finding the Fourth Proportional to 2,111.35, 3,166.97 and 878.43

Step by Step Solution

1. Step 1: Write the proportion equation
   2,111.35 : 3,166.97 = 878.43 : x
2. Step 2: Convert to fraction form
   2,111.35/3,166.97 = 878.43/x
3. Step 3: Cross multiply
   2,111.35x = 3,166.97 × 878.43
4. Step 4: Simplify right side
   2,111.35x = 2,781,951.13
5. Step 5: Solve for x
   x = 2,781,951.13/2,111.35
6. Step 6: Final answer
   x = 1,317.62