Finding the Fourth Proportional to 1,442.49, 1,989.88 and 911.18

Step by Step Solution

1. Step 1: Write the proportion equation
   1,442.49 : 1,989.88 = 911.18 : x
2. Step 2: Convert to fraction form
   1,442.49/1,989.88 = 911.18/x
3. Step 3: Cross multiply
   1,442.49x = 1,989.88 × 911.18
4. Step 4: Simplify right side
   1,442.49x = 1,813,138.86
5. Step 5: Solve for x
   x = 1,813,138.86/1,442.49
6. Step 6: Final answer
   x = 1,256.95