Finding the Fourth Proportional to 2,196.71, 3,291.86 and 808.56

Step by Step Solution

1. Step 1: Write the proportion equation
   2,196.71 : 3,291.86 = 808.56 : x
2. Step 2: Convert to fraction form
   2,196.71/3,291.86 = 808.56/x
3. Step 3: Cross multiply
   2,196.71x = 3,291.86 × 808.56
4. Step 4: Simplify right side
   2,196.71x = 2,661,662.28
5. Step 5: Solve for x
   x = 2,661,662.28/2,196.71
6. Step 6: Final answer
   x = 1,211.66