Finding the Fourth Proportional to 1,158.54, 1,598.79 and 661.15

Step by Step Solution

1. Step 1: Write the proportion equation
   1,158.54 : 1,598.79 = 661.15 : x
2. Step 2: Convert to fraction form
   1,158.54/1,598.79 = 661.15/x
3. Step 3: Cross multiply
   1,158.54x = 1,598.79 × 661.15
4. Step 4: Simplify right side
   1,158.54x = 1,057,040.01
5. Step 5: Solve for x
   x = 1,057,040.01/1,158.54
6. Step 6: Final answer
   x = 912.39