Finding the Fourth Proportional to 2,106.61, 3,157.55 and 789.09

Step by Step Solution

1. Step 1: Write the proportion equation
   2,106.61 : 3,157.55 = 789.09 : x
2. Step 2: Convert to fraction form
   2,106.61/3,157.55 = 789.09/x
3. Step 3: Cross multiply
   2,106.61x = 3,157.55 × 789.09
4. Step 4: Simplify right side
   2,106.61x = 2,491,593.10
5. Step 5: Solve for x
   x = 2,491,593.10/2,106.61
6. Step 6: Final answer
   x = 1,182.75