Finding the Fourth Proportional to 2,419.05, 3,628.85 and 858.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,419.05 : 3,628.85 = 858.72 : x
2. Step 2: Convert to fraction form
   2,419.05/3,628.85 = 858.72/x
3. Step 3: Cross multiply
   2,419.05x = 3,628.85 × 858.72
4. Step 4: Simplify right side
   2,419.05x = 3,116,161.78
5. Step 5: Solve for x
   x = 3,116,161.78/2,419.05
6. Step 6: Final answer
   x = 1,288.18