Finding the Fourth Proportional to 3,921.81, 5,411.98 and 2,153.37

Step by Step Solution

1. Step 1: Write the proportion equation
   3,921.81 : 5,411.98 = 2,153.37 : x
2. Step 2: Convert to fraction form
   3,921.81/5,411.98 = 2,153.37/x
3. Step 3: Cross multiply
   3,921.81x = 5,411.98 × 2,153.37
4. Step 4: Simplify right side
   3,921.81x = 11,653,995.37
5. Step 5: Solve for x
   x = 11,653,995.37/3,921.81
6. Step 6: Final answer
   x = 2,971.59