Finding the Fourth Proportional to 1,361.96, 1,879.60 and 772.56

Step by Step Solution

1. Step 1: Write the proportion equation
   1,361.96 : 1,879.60 = 772.56 : x
2. Step 2: Convert to fraction form
   1,361.96/1,879.60 = 772.56/x
3. Step 3: Cross multiply
   1,361.96x = 1,879.60 × 772.56
4. Step 4: Simplify right side
   1,361.96x = 1,452,103.78
5. Step 5: Solve for x
   x = 1,452,103.78/1,361.96
6. Step 6: Final answer
   x = 1,066.19