Finding the Fourth Proportional to 2,196.57, 3,291.39 and 807.99

Step by Step Solution

1. Step 1: Write the proportion equation
   2,196.57 : 3,291.39 = 807.99 : x
2. Step 2: Convert to fraction form
   2,196.57/3,291.39 = 807.99/x
3. Step 3: Cross multiply
   2,196.57x = 3,291.39 × 807.99
4. Step 4: Simplify right side
   2,196.57x = 2,659,410.21
5. Step 5: Solve for x
   x = 2,659,410.21/2,196.57
6. Step 6: Final answer
   x = 1,210.71