Finding the Fourth Proportional to 1,223.94, 1,687.86 and 804.57

Step by Step Solution

1. Step 1: Write the proportion equation
   1,223.94 : 1,687.86 = 804.57 : x
2. Step 2: Convert to fraction form
   1,223.94/1,687.86 = 804.57/x
3. Step 3: Cross multiply
   1,223.94x = 1,687.86 × 804.57
4. Step 4: Simplify right side
   1,223.94x = 1,358,001.52
5. Step 5: Solve for x
   x = 1,358,001.52/1,223.94
6. Step 6: Final answer
   x = 1,109.53