Finding the Fourth Proportional to 2,105.91, 3,157.83 and 789.86

Step by Step Solution

1. Step 1: Write the proportion equation
   2,105.91 : 3,157.83 = 789.86 : x
2. Step 2: Convert to fraction form
   2,105.91/3,157.83 = 789.86/x
3. Step 3: Cross multiply
   2,105.91x = 3,157.83 × 789.86
4. Step 4: Simplify right side
   2,105.91x = 2,494,243.60
5. Step 5: Solve for x
   x = 2,494,243.60/2,105.91
6. Step 6: Final answer
   x = 1,184.40