Finding the Fourth Proportional to 12,383.40, 17,086.51 and 7,904.31

Step by Step Solution

1. Step 1: Write the proportion equation
   12,383.40 : 17,086.51 = 7,904.31 : x
2. Step 2: Convert to fraction form
   12,383.40/17,086.51 = 7,904.31/x
3. Step 3: Cross multiply
   12,383.40x = 17,086.51 × 7,904.31
4. Step 4: Simplify right side
   12,383.40x = 135,057,071.86
5. Step 5: Solve for x
   x = 135,057,071.86/12,383.40
6. Step 6: Final answer
   x = 10,906.30