Finding the Fourth Proportional to 1,361.79, 1,879.20 and 772.38

Step by Step Solution

1. Step 1: Write the proportion equation
   1,361.79 : 1,879.20 = 772.38 : x
2. Step 2: Convert to fraction form
   1,361.79/1,879.20 = 772.38/x
3. Step 3: Cross multiply
   1,361.79x = 1,879.20 × 772.38
4. Step 4: Simplify right side
   1,361.79x = 1,451,456.50
5. Step 5: Solve for x
   x = 1,451,456.50/1,361.79
6. Step 6: Final answer
   x = 1,065.84