Finding the Fourth Proportional to 2,309.25, 3,186.77 and 1,261.31

Step by Step Solution

1. Step 1: Write the proportion equation
   2,309.25 : 3,186.77 = 1,261.31 : x
2. Step 2: Convert to fraction form
   2,309.25/3,186.77 = 1,261.31/x
3. Step 3: Cross multiply
   2,309.25x = 3,186.77 × 1,261.31
4. Step 4: Simplify right side
   2,309.25x = 4,019,506.53
5. Step 5: Solve for x
   x = 4,019,506.53/2,309.25
6. Step 6: Final answer
   x = 1,740.61