Finding the Fourth Proportional to 2,662.90, 3,994.83 and 813.98

Step by Step Solution

1. Step 1: Write the proportion equation
   2,662.90 : 3,994.83 = 813.98 : x
2. Step 2: Convert to fraction form
   2,662.90/3,994.83 = 813.98/x
3. Step 3: Cross multiply
   2,662.90x = 3,994.83 × 813.98
4. Step 4: Simplify right side
   2,662.90x = 3,251,721.71
5. Step 5: Solve for x
   x = 3,251,721.71/2,662.90
6. Step 6: Final answer
   x = 1,221.12