Finding the Fourth Proportional to 911.88, 1,258.55 and 538.83

Step by Step Solution

1. Step 1: Write the proportion equation
   911.88 : 1,258.55 = 538.83 : x
2. Step 2: Convert to fraction form
   911.88/1,258.55 = 538.83/x
3. Step 3: Cross multiply
   911.88x = 1,258.55 × 538.83
4. Step 4: Simplify right side
   911.88x = 678,139.10
5. Step 5: Solve for x
   x = 678,139.10/911.88
6. Step 6: Final answer
   x = 743.67