Finding the Fourth Proportional to 1,158.50, 1,738.31 and 509.15

Step by Step Solution

1. Step 1: Write the proportion equation
   1,158.50 : 1,738.31 = 509.15 : x
2. Step 2: Convert to fraction form
   1,158.50/1,738.31 = 509.15/x
3. Step 3: Cross multiply
   1,158.50x = 1,738.31 × 509.15
4. Step 4: Simplify right side
   1,158.50x = 885,049.30
5. Step 5: Solve for x
   x = 885,049.30/1,158.50
6. Step 6: Final answer
   x = 763.96