Finding the Fourth Proportional to 1,379.31, 1,903.53 and 789.83

Step by Step Solution

1. Step 1: Write the proportion equation
   1,379.31 : 1,903.53 = 789.83 : x
2. Step 2: Convert to fraction form
   1,379.31/1,903.53 = 789.83/x
3. Step 3: Cross multiply
   1,379.31x = 1,903.53 × 789.83
4. Step 4: Simplify right side
   1,379.31x = 1,503,455.58
5. Step 5: Solve for x
   x = 1,503,455.58/1,379.31
6. Step 6: Final answer
   x = 1,090.01