Finding the Fourth Proportional to 2,644.16, 3,964.60 and 1,821.50

Step by Step Solution

1. Step 1: Write the proportion equation
   2,644.16 : 3,964.60 = 1,821.50 : x
2. Step 2: Convert to fraction form
   2,644.16/3,964.60 = 1,821.50/x
3. Step 3: Cross multiply
   2,644.16x = 3,964.60 × 1,821.50
4. Step 4: Simplify right side
   2,644.16x = 7,221,528.28
5. Step 5: Solve for x
   x = 7,221,528.28/2,644.16
6. Step 6: Final answer
   x = 2,731.12