Finding the Fourth Proportional to 1,145.90, 1,581.32 and 648.53

Step by Step Solution

1. Step 1: Write the proportion equation
   1,145.90 : 1,581.32 = 648.53 : x
2. Step 2: Convert to fraction form
   1,145.90/1,581.32 = 648.53/x
3. Step 3: Cross multiply
   1,145.90x = 1,581.32 × 648.53
4. Step 4: Simplify right side
   1,145.90x = 1,025,533.46
5. Step 5: Solve for x
   x = 1,025,533.46/1,145.90
6. Step 6: Final answer
   x = 894.96