Finding the Fourth Proportional to 2,131.33, 3,198.12 and 815.98

Step by Step Solution

1. Step 1: Write the proportion equation
   2,131.33 : 3,198.12 = 815.98 : x
2. Step 2: Convert to fraction form
   2,131.33/3,198.12 = 815.98/x
3. Step 3: Cross multiply
   2,131.33x = 3,198.12 × 815.98
4. Step 4: Simplify right side
   2,131.33x = 2,609,601.96
5. Step 5: Solve for x
   x = 2,609,601.96/2,131.33
6. Step 6: Final answer
   x = 1,224.40