Finding the Fourth Proportional to 1,158.79, 1,598.87 and 686.45

Step by Step Solution

1. Step 1: Write the proportion equation
   1,158.79 : 1,598.87 = 686.45 : x
2. Step 2: Convert to fraction form
   1,158.79/1,598.87 = 686.45/x
3. Step 3: Cross multiply
   1,158.79x = 1,598.87 × 686.45
4. Step 4: Simplify right side
   1,158.79x = 1,097,544.31
5. Step 5: Solve for x
   x = 1,097,544.31/1,158.79
6. Step 6: Final answer
   x = 947.15