Finding the Fourth Proportional to 1,143.07, 1,577.52 and 645.94

Step by Step Solution

1. Step 1: Write the proportion equation
   1,143.07 : 1,577.52 = 645.94 : x
2. Step 2: Convert to fraction form
   1,143.07/1,577.52 = 645.94/x
3. Step 3: Cross multiply
   1,143.07x = 1,577.52 × 645.94
4. Step 4: Simplify right side
   1,143.07x = 1,018,983.27
5. Step 5: Solve for x
   x = 1,018,983.27/1,143.07
6. Step 6: Final answer
   x = 891.44