Finding the Fourth Proportional to 1,145.81, 1,581.32 and 648.68

Step by Step Solution

1. Step 1: Write the proportion equation
   1,145.81 : 1,581.32 = 648.68 : x
2. Step 2: Convert to fraction form
   1,145.81/1,581.32 = 648.68/x
3. Step 3: Cross multiply
   1,145.81x = 1,581.32 × 648.68
4. Step 4: Simplify right side
   1,145.81x = 1,025,764.37
5. Step 5: Solve for x
   x = 1,025,764.37/1,145.81
6. Step 6: Final answer
   x = 895.23