Finding the Fourth Proportional to 2,053.78, 3,081.89 and 821.00

Step by Step Solution

1. Step 1: Write the proportion equation
   2,053.78 : 3,081.89 = 821.00 : x
2. Step 2: Convert to fraction form
   2,053.78/3,081.89 = 821.00/x
3. Step 3: Cross multiply
   2,053.78x = 3,081.89 × 821.00
4. Step 4: Simplify right side
   2,053.78x = 2,530,241.45
5. Step 5: Solve for x
   x = 2,530,241.45/2,053.78
6. Step 6: Final answer
   x = 1,231.99