Finding the Fourth Proportional to 2,155.78, 2,974.78 and 1,198.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,155.78 : 2,974.78 = 1,198.72 : x
2. Step 2: Convert to fraction form
   2,155.78/2,974.78 = 1,198.72/x
3. Step 3: Cross multiply
   2,155.78x = 2,974.78 × 1,198.72
4. Step 4: Simplify right side
   2,155.78x = 3,565,928.28
5. Step 5: Solve for x
   x = 3,565,928.28/2,155.78
6. Step 6: Final answer
   x = 1,654.12