Finding the Fourth Proportional to 2,142.78, 3,217.12 and 1,103.64

Step by Step Solution

1. Step 1: Write the proportion equation
   2,142.78 : 3,217.12 = 1,103.64 : x
2. Step 2: Convert to fraction form
   2,142.78/3,217.12 = 1,103.64/x
3. Step 3: Cross multiply
   2,142.78x = 3,217.12 × 1,103.64
4. Step 4: Simplify right side
   2,142.78x = 3,550,542.32
5. Step 5: Solve for x
   x = 3,550,542.32/2,142.78
6. Step 6: Final answer
   x = 1,656.98