Finding the Fourth Proportional to 2,664.30, 3,990.64 and 2,196.84

Step by Step Solution

1. Step 1: Write the proportion equation
   2,664.30 : 3,990.64 = 2,196.84 : x
2. Step 2: Convert to fraction form
   2,664.30/3,990.64 = 2,196.84/x
3. Step 3: Cross multiply
   2,664.30x = 3,990.64 × 2,196.84
4. Step 4: Simplify right side
   2,664.30x = 8,766,797.58
5. Step 5: Solve for x
   x = 8,766,797.58/2,664.30
6. Step 6: Final answer
   x = 3,290.47