Finding the Fourth Proportional to 1,623.78, 2,240.55 and 994.41

Step by Step Solution

1. Step 1: Write the proportion equation
   1,623.78 : 2,240.55 = 994.41 : x
2. Step 2: Convert to fraction form
   1,623.78/2,240.55 = 994.41/x
3. Step 3: Cross multiply
   1,623.78x = 2,240.55 × 994.41
4. Step 4: Simplify right side
   1,623.78x = 2,228,025.33
5. Step 5: Solve for x
   x = 2,228,025.33/1,623.78
6. Step 6: Final answer
   x = 1,372.12