Finding the Fourth Proportional to 1,418.89, 1,958.38 and 789.63

Step by Step Solution

1. Step 1: Write the proportion equation
   1,418.89 : 1,958.38 = 789.63 : x
2. Step 2: Convert to fraction form
   1,418.89/1,958.38 = 789.63/x
3. Step 3: Cross multiply
   1,418.89x = 1,958.38 × 789.63
4. Step 4: Simplify right side
   1,418.89x = 1,546,395.60
5. Step 5: Solve for x
   x = 1,546,395.60/1,418.89
6. Step 6: Final answer
   x = 1,089.86