Finding the Fourth Proportional to 2,535.15, 3,802.31 and 891.31

Step by Step Solution

1. Step 1: Write the proportion equation
   2,535.15 : 3,802.31 = 891.31 : x
2. Step 2: Convert to fraction form
   2,535.15/3,802.31 = 891.31/x
3. Step 3: Cross multiply
   2,535.15x = 3,802.31 × 891.31
4. Step 4: Simplify right side
   2,535.15x = 3,389,036.93
5. Step 5: Solve for x
   x = 3,389,036.93/2,535.15
6. Step 6: Final answer
   x = 1,336.82