Finding the Fourth Proportional to 2,144.82, 3,215.80 and 911.91

Step by Step Solution

1. Step 1: Write the proportion equation
   2,144.82 : 3,215.80 = 911.91 : x
2. Step 2: Convert to fraction form
   2,144.82/3,215.80 = 911.91/x
3. Step 3: Cross multiply
   2,144.82x = 3,215.80 × 911.91
4. Step 4: Simplify right side
   2,144.82x = 2,932,520.18
5. Step 5: Solve for x
   x = 2,932,520.18/2,144.82
6. Step 6: Final answer
   x = 1,367.26