Finding the Fourth Proportional to 1,158.49, 1,598.90 and 661.15

Step by Step Solution

1. Step 1: Write the proportion equation
   1,158.49 : 1,598.90 = 661.15 : x
2. Step 2: Convert to fraction form
   1,158.49/1,598.90 = 661.15/x
3. Step 3: Cross multiply
   1,158.49x = 1,598.90 × 661.15
4. Step 4: Simplify right side
   1,158.49x = 1,057,112.74
5. Step 5: Solve for x
   x = 1,057,112.74/1,158.49
6. Step 6: Final answer
   x = 912.49