Finding the Fourth Proportional to 1,419.27, 1,958.59 and 789.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,419.27 : 1,958.59 = 789.78 : x
2. Step 2: Convert to fraction form
   1,419.27/1,958.59 = 789.78/x
3. Step 3: Cross multiply
   1,419.27x = 1,958.59 × 789.78
4. Step 4: Simplify right side
   1,419.27x = 1,546,855.21
5. Step 5: Solve for x
   x = 1,546,855.21/1,419.27
6. Step 6: Final answer
   x = 1,089.89