Finding the Fourth Proportional to 2,235.07, 3,084.31 and 1,290.90

Step by Step Solution

1. Step 1: Write the proportion equation
   2,235.07 : 3,084.31 = 1,290.90 : x
2. Step 2: Convert to fraction form
   2,235.07/3,084.31 = 1,290.90/x
3. Step 3: Cross multiply
   2,235.07x = 3,084.31 × 1,290.90
4. Step 4: Simplify right side
   2,235.07x = 3,981,535.78
5. Step 5: Solve for x
   x = 3,981,535.78/2,235.07
6. Step 6: Final answer
   x = 1,781.39