Finding the Fourth Proportional to 1,361.89, 1,879.17 and 772.30

Step by Step Solution

1. Step 1: Write the proportion equation
   1,361.89 : 1,879.17 = 772.30 : x
2. Step 2: Convert to fraction form
   1,361.89/1,879.17 = 772.30/x
3. Step 3: Cross multiply
   1,361.89x = 1,879.17 × 772.30
4. Step 4: Simplify right side
   1,361.89x = 1,451,282.99
5. Step 5: Solve for x
   x = 1,451,282.99/1,361.89
6. Step 6: Final answer
   x = 1,065.64