Finding the Fourth Proportional to 1,361.89, 1,879.53 and 772.61

Step by Step Solution

1. Step 1: Write the proportion equation
   1,361.89 : 1,879.53 = 772.61 : x
2. Step 2: Convert to fraction form
   1,361.89/1,879.53 = 772.61/x
3. Step 3: Cross multiply
   1,361.89x = 1,879.53 × 772.61
4. Step 4: Simplify right side
   1,361.89x = 1,452,143.67
5. Step 5: Solve for x
   x = 1,452,143.67/1,361.89
6. Step 6: Final answer
   x = 1,066.27