Finding the Fourth Proportional to 3,921.57, 5,411.84 and 2,153.25

Step by Step Solution

1. Step 1: Write the proportion equation
   3,921.57 : 5,411.84 = 2,153.25 : x
2. Step 2: Convert to fraction form
   3,921.57/5,411.84 = 2,153.25/x
3. Step 3: Cross multiply
   3,921.57x = 5,411.84 × 2,153.25
4. Step 4: Simplify right side
   3,921.57x = 11,653,033.71
5. Step 5: Solve for x
   x = 11,653,033.71/3,921.57
6. Step 6: Final answer
   x = 2,971.52