Finding the Fourth Proportional to 1,561.10, 2,155.02 and 994.18

Step by Step Solution

1. Step 1: Write the proportion equation
   1,561.10 : 2,155.02 = 994.18 : x
2. Step 2: Convert to fraction form
   1,561.10/2,155.02 = 994.18/x
3. Step 3: Cross multiply
   1,561.10x = 2,155.02 × 994.18
4. Step 4: Simplify right side
   1,561.10x = 2,142,477.78
5. Step 5: Solve for x
   x = 2,142,477.78/1,561.10
6. Step 6: Final answer
   x = 1,372.42