Finding the Fourth Proportional to 3,191.79, 4,789.87 and 1,111.78

Step by Step Solution

1. Step 1: Write the proportion equation
   3,191.79 : 4,789.87 = 1,111.78 : x
2. Step 2: Convert to fraction form
   3,191.79/4,789.87 = 1,111.78/x
3. Step 3: Cross multiply
   3,191.79x = 4,789.87 × 1,111.78
4. Step 4: Simplify right side
   3,191.79x = 5,325,281.67
5. Step 5: Solve for x
   x = 5,325,281.67/3,191.79
6. Step 6: Final answer
   x = 1,668.43