Finding the Fourth Proportional to 3,391.39, 5,086.55 and 1,312.35

Step by Step Solution

1. Step 1: Write the proportion equation
   3,391.39 : 5,086.55 = 1,312.35 : x
2. Step 2: Convert to fraction form
   3,391.39/5,086.55 = 1,312.35/x
3. Step 3: Cross multiply
   3,391.39x = 5,086.55 × 1,312.35
4. Step 4: Simplify right side
   3,391.39x = 6,675,333.89
5. Step 5: Solve for x
   x = 6,675,333.89/3,391.39
6. Step 6: Final answer
   x = 1,968.32