Finding the Fourth Proportional to 1,143.83, 1,578.58 and 646.57

Step by Step Solution

1. Step 1: Write the proportion equation
   1,143.83 : 1,578.58 = 646.57 : x
2. Step 2: Convert to fraction form
   1,143.83/1,578.58 = 646.57/x
3. Step 3: Cross multiply
   1,143.83x = 1,578.58 × 646.57
4. Step 4: Simplify right side
   1,143.83x = 1,020,662.47
5. Step 5: Solve for x
   x = 1,020,662.47/1,143.83
6. Step 6: Final answer
   x = 892.32