Finding the Fourth Proportional to 5,419.53, 8,128.89 and 1,956.78

Step by Step Solution

1. Step 1: Write the proportion equation
   5,419.53 : 8,128.89 = 1,956.78 : x
2. Step 2: Convert to fraction form
   5,419.53/8,128.89 = 1,956.78/x
3. Step 3: Cross multiply
   5,419.53x = 8,128.89 × 1,956.78
4. Step 4: Simplify right side
   5,419.53x = 15,906,449.37
5. Step 5: Solve for x
   x = 15,906,449.37/5,419.53
6. Step 6: Final answer
   x = 2,935.02