Finding the Fourth Proportional to 2,571.64, 3,855.94 and 816.17

Step by Step Solution

1. Step 1: Write the proportion equation
   2,571.64 : 3,855.94 = 816.17 : x
2. Step 2: Convert to fraction form
   2,571.64/3,855.94 = 816.17/x
3. Step 3: Cross multiply
   2,571.64x = 3,855.94 × 816.17
4. Step 4: Simplify right side
   2,571.64x = 3,147,081.23
5. Step 5: Solve for x
   x = 3,147,081.23/2,571.64
6. Step 6: Final answer
   x = 1,223.77