Finding the Fourth Proportional to 1,362.24, 1,879.89 and 772.80

Step by Step Solution

1. Step 1: Write the proportion equation
   1,362.24 : 1,879.89 = 772.80 : x
2. Step 2: Convert to fraction form
   1,362.24/1,879.89 = 772.80/x
3. Step 3: Cross multiply
   1,362.24x = 1,879.89 × 772.80
4. Step 4: Simplify right side
   1,362.24x = 1,452,778.99
5. Step 5: Solve for x
   x = 1,452,778.99/1,362.24
6. Step 6: Final answer
   x = 1,066.46