Finding the Fourth Proportional to 3,892.16, 5,371.16 and 2,123.80

Step by Step Solution

1. Step 1: Write the proportion equation
   3,892.16 : 5,371.16 = 2,123.80 : x
2. Step 2: Convert to fraction form
   3,892.16/5,371.16 = 2,123.80/x
3. Step 3: Cross multiply
   3,892.16x = 5,371.16 × 2,123.80
4. Step 4: Simplify right side
   3,892.16x = 11,407,269.61
5. Step 5: Solve for x
   x = 11,407,269.61/3,892.16
6. Step 6: Final answer
   x = 2,930.83