Finding the Fourth Proportional to 1,426.80, 2,139.78 and 942.42

Step by Step Solution

1. Step 1: Write the proportion equation
   1,426.80 : 2,139.78 = 942.42 : x
2. Step 2: Convert to fraction form
   1,426.80/2,139.78 = 942.42/x
3. Step 3: Cross multiply
   1,426.80x = 2,139.78 × 942.42
4. Step 4: Simplify right side
   1,426.80x = 2,016,571.47
5. Step 5: Solve for x
   x = 2,016,571.47/1,426.80
6. Step 6: Final answer
   x = 1,413.35