Finding the Fourth Proportional to 2,644.21, 3,966.27 and 912.79

Step by Step Solution

1. Step 1: Write the proportion equation
   2,644.21 : 3,966.27 = 912.79 : x
2. Step 2: Convert to fraction form
   2,644.21/3,966.27 = 912.79/x
3. Step 3: Cross multiply
   2,644.21x = 3,966.27 × 912.79
4. Step 4: Simplify right side
   2,644.21x = 3,620,371.59
5. Step 5: Solve for x
   x = 3,620,371.59/2,644.21
6. Step 6: Final answer
   x = 1,369.17