Finding the Fourth Proportional to 1,078.69, 1,485.24 and 813.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,078.69 : 1,485.24 = 813.50 : x
2. Step 2: Convert to fraction form
   1,078.69/1,485.24 = 813.50/x
3. Step 3: Cross multiply
   1,078.69x = 1,485.24 × 813.50
4. Step 4: Simplify right side
   1,078.69x = 1,208,242.74
5. Step 5: Solve for x
   x = 1,208,242.74/1,078.69
6. Step 6: Final answer
   x = 1,120.10