Finding the Fourth Proportional to 1,393.89, 1,922.62 and 804.21

Step by Step Solution

1. Step 1: Write the proportion equation
   1,393.89 : 1,922.62 = 804.21 : x
2. Step 2: Convert to fraction form
   1,393.89/1,922.62 = 804.21/x
3. Step 3: Cross multiply
   1,393.89x = 1,922.62 × 804.21
4. Step 4: Simplify right side
   1,393.89x = 1,546,190.23
5. Step 5: Solve for x
   x = 1,546,190.23/1,393.89
6. Step 6: Final answer
   x = 1,109.26