Finding the Fourth Proportional to 1,408.37, 1,942.90 and 911.17

Step by Step Solution

1. Step 1: Write the proportion equation
   1,408.37 : 1,942.90 = 911.17 : x
2. Step 2: Convert to fraction form
   1,408.37/1,942.90 = 911.17/x
3. Step 3: Cross multiply
   1,408.37x = 1,942.90 × 911.17
4. Step 4: Simplify right side
   1,408.37x = 1,770,301.41
5. Step 5: Solve for x
   x = 1,770,301.41/1,408.37
6. Step 6: Final answer
   x = 1,256.99