Finding the Fourth Proportional to 1,362.28, 1,879.90 and 772.81

Step by Step Solution

1. Step 1: Write the proportion equation
   1,362.28 : 1,879.90 = 772.81 : x
2. Step 2: Convert to fraction form
   1,362.28/1,879.90 = 772.81/x
3. Step 3: Cross multiply
   1,362.28x = 1,879.90 × 772.81
4. Step 4: Simplify right side
   1,362.28x = 1,452,805.52
5. Step 5: Solve for x
   x = 1,452,805.52/1,362.28
6. Step 6: Final answer
   x = 1,066.45