Finding the Fourth Proportional to 1,383.30, 1,908.15 and 885.75

Step by Step Solution

1. Step 1: Write the proportion equation
   1,383.30 : 1,908.15 = 885.75 : x
2. Step 2: Convert to fraction form
   1,383.30/1,908.15 = 885.75/x
3. Step 3: Cross multiply
   1,383.30x = 1,908.15 × 885.75
4. Step 4: Simplify right side
   1,383.30x = 1,690,143.86
5. Step 5: Solve for x
   x = 1,690,143.86/1,383.30
6. Step 6: Final answer
   x = 1,221.82