Finding the Fourth Proportional to 1,383.30, 1,908.78 and 785.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,383.30 : 1,908.78 = 785.78 : x
2. Step 2: Convert to fraction form
   1,383.30/1,908.78 = 785.78/x
3. Step 3: Cross multiply
   1,383.30x = 1,908.78 × 785.78
4. Step 4: Simplify right side
   1,383.30x = 1,499,881.15
5. Step 5: Solve for x
   x = 1,499,881.15/1,383.30
6. Step 6: Final answer
   x = 1,084.28