Finding the Fourth Proportional to 3,892.15, 5,371.18 and 2,123.79

Step by Step Solution

1. Step 1: Write the proportion equation
   3,892.15 : 5,371.18 = 2,123.79 : x
2. Step 2: Convert to fraction form
   3,892.15/5,371.18 = 2,123.79/x
3. Step 3: Cross multiply
   3,892.15x = 5,371.18 × 2,123.79
4. Step 4: Simplify right side
   3,892.15x = 11,407,258.37
5. Step 5: Solve for x
   x = 11,407,258.37/3,892.15
6. Step 6: Final answer
   x = 2,930.84