Finding the Fourth Proportional to 3,926.56, 5,418.72 and 2,158.22

Step by Step Solution

1. Step 1: Write the proportion equation
   3,926.56 : 5,418.72 = 2,158.22 : x
2. Step 2: Convert to fraction form
   3,926.56/5,418.72 = 2,158.22/x
3. Step 3: Cross multiply
   3,926.56x = 5,418.72 × 2,158.22
4. Step 4: Simplify right side
   3,926.56x = 11,694,789.88
5. Step 5: Solve for x
   x = 11,694,789.88/3,926.56
6. Step 6: Final answer
   x = 2,978.38