Finding the Fourth Proportional to 2,309.31, 3,186.88 and 1,261.37

Step by Step Solution

1. Step 1: Write the proportion equation
   2,309.31 : 3,186.88 = 1,261.37 : x
2. Step 2: Convert to fraction form
   2,309.31/3,186.88 = 1,261.37/x
3. Step 3: Cross multiply
   2,309.31x = 3,186.88 × 1,261.37
4. Step 4: Simplify right side
   2,309.31x = 4,019,839.64
5. Step 5: Solve for x
   x = 4,019,839.64/2,309.31
6. Step 6: Final answer
   x = 1,740.71