Finding the Fourth Proportional to 1,392.89, 1,922.40 and 803.61

Step by Step Solution

1. Step 1: Write the proportion equation
   1,392.89 : 1,922.40 = 803.61 : x
2. Step 2: Convert to fraction form
   1,392.89/1,922.40 = 803.61/x
3. Step 3: Cross multiply
   1,392.89x = 1,922.40 × 803.61
4. Step 4: Simplify right side
   1,392.89x = 1,544,859.86
5. Step 5: Solve for x
   x = 1,544,859.86/1,392.89
6. Step 6: Final answer
   x = 1,109.11