Finding the Fourth Proportional to 2,643.10, 3,964.52 and 911.68

Step by Step Solution

1. Step 1: Write the proportion equation
   2,643.10 : 3,964.52 = 911.68 : x
2. Step 2: Convert to fraction form
   2,643.10/3,964.52 = 911.68/x
3. Step 3: Cross multiply
   2,643.10x = 3,964.52 × 911.68
4. Step 4: Simplify right side
   2,643.10x = 3,614,373.59
5. Step 5: Solve for x
   x = 3,614,373.59/2,643.10
6. Step 6: Final answer
   x = 1,367.48