Finding the Fourth Proportional to 1,362.20, 1,879.76 and 772.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,362.20 : 1,879.76 = 772.72 : x
2. Step 2: Convert to fraction form
   1,362.20/1,879.76 = 772.72/x
3. Step 3: Cross multiply
   1,362.20x = 1,879.76 × 772.72
4. Step 4: Simplify right side
   1,362.20x = 1,452,525.38
5. Step 5: Solve for x
   x = 1,452,525.38/1,362.20
6. Step 6: Final answer
   x = 1,066.31