Finding the Fourth Proportional to 1,158.18, 1,736.91 and 388.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,158.18 : 1,736.91 = 388.50 : x
2. Step 2: Convert to fraction form
   1,158.18/1,736.91 = 388.50/x
3. Step 3: Cross multiply
   1,158.18x = 1,736.91 × 388.50
4. Step 4: Simplify right side
   1,158.18x = 674,789.54
5. Step 5: Solve for x
   x = 674,789.54/1,158.18
6. Step 6: Final answer
   x = 582.63