Finding the Fourth Proportional to 1,019.52, 1,528.32 and 858.24

Step by Step Solution

1. Step 1: Write the proportion equation
   1,019.52 : 1,528.32 = 858.24 : x
2. Step 2: Convert to fraction form
   1,019.52/1,528.32 = 858.24/x
3. Step 3: Cross multiply
   1,019.52x = 1,528.32 × 858.24
4. Step 4: Simplify right side
   1,019.52x = 1,311,665.36
5. Step 5: Solve for x
   x = 1,311,665.36/1,019.52
6. Step 6: Final answer
   x = 1,286.55