Finding the Fourth Proportional to 1,145.71, 1,581.16 and 648.35

Step by Step Solution

1. Step 1: Write the proportion equation
   1,145.71 : 1,581.16 = 648.35 : x
2. Step 2: Convert to fraction form
   1,145.71/1,581.16 = 648.35/x
3. Step 3: Cross multiply
   1,145.71x = 1,581.16 × 648.35
4. Step 4: Simplify right side
   1,145.71x = 1,025,133.94
5. Step 5: Solve for x
   x = 1,025,133.94/1,145.71
6. Step 6: Final answer
   x = 894.76