Finding the Fourth Proportional to 1,383.49, 1,908.54 and 823.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,383.49 : 1,908.54 = 823.78 : x
2. Step 2: Convert to fraction form
   1,383.49/1,908.54 = 823.78/x
3. Step 3: Cross multiply
   1,383.49x = 1,908.54 × 823.78
4. Step 4: Simplify right side
   1,383.49x = 1,572,207.54
5. Step 5: Solve for x
   x = 1,572,207.54/1,383.49
6. Step 6: Final answer
   x = 1,136.41