Finding the Fourth Proportional to 2,144.68, 3,216.71 and 911.45

Step by Step Solution

1. Step 1: Write the proportion equation
   2,144.68 : 3,216.71 = 911.45 : x
2. Step 2: Convert to fraction form
   2,144.68/3,216.71 = 911.45/x
3. Step 3: Cross multiply
   2,144.68x = 3,216.71 × 911.45
4. Step 4: Simplify right side
   2,144.68x = 2,931,880.65
5. Step 5: Solve for x
   x = 2,931,880.65/2,144.68
6. Step 6: Final answer
   x = 1,367.05