Finding the Fourth Proportional to 1,378.53, 1,902.42 and 789.24

Step by Step Solution

1. Step 1: Write the proportion equation
   1,378.53 : 1,902.42 = 789.24 : x
2. Step 2: Convert to fraction form
   1,378.53/1,902.42 = 789.24/x
3. Step 3: Cross multiply
   1,378.53x = 1,902.42 × 789.24
4. Step 4: Simplify right side
   1,378.53x = 1,501,465.96
5. Step 5: Solve for x
   x = 1,501,465.96/1,378.53
6. Step 6: Final answer
   x = 1,089.18