Finding the Fourth Proportional to 2,391.78, 3,300.90 and 1,397.37

Step by Step Solution

1. Step 1: Write the proportion equation
   2,391.78 : 3,300.90 = 1,397.37 : x
2. Step 2: Convert to fraction form
   2,391.78/3,300.90 = 1,397.37/x
3. Step 3: Cross multiply
   2,391.78x = 3,300.90 × 1,397.37
4. Step 4: Simplify right side
   2,391.78x = 4,612,578.63
5. Step 5: Solve for x
   x = 4,612,578.63/2,391.78
6. Step 6: Final answer
   x = 1,928.51