Finding the Fourth Proportional to 1,396.36, 1,921.84 and 1,115.68

Step by Step Solution

1. Step 1: Write the proportion equation
   1,396.36 : 1,921.84 = 1,115.68 : x
2. Step 2: Convert to fraction form
   1,396.36/1,921.84 = 1,115.68/x
3. Step 3: Cross multiply
   1,396.36x = 1,921.84 × 1,115.68
4. Step 4: Simplify right side
   1,396.36x = 2,144,158.45
5. Step 5: Solve for x
   x = 2,144,158.45/1,396.36
6. Step 6: Final answer
   x = 1,535.53