Finding the Fourth Proportional to 3,926.72, 5,418.42 and 2,158.22

Step by Step Solution

1. Step 1: Write the proportion equation
   3,926.72 : 5,418.42 = 2,158.22 : x
2. Step 2: Convert to fraction form
   3,926.72/5,418.42 = 2,158.22/x
3. Step 3: Cross multiply
   3,926.72x = 5,418.42 × 2,158.22
4. Step 4: Simplify right side
   3,926.72x = 11,694,142.41
5. Step 5: Solve for x
   x = 11,694,142.41/3,926.72
6. Step 6: Final answer
   x = 2,978.09