Finding the Fourth Proportional to 3,896.38, 5,376.99 and 2,128.15

Step by Step Solution

1. Step 1: Write the proportion equation
   3,896.38 : 5,376.99 = 2,128.15 : x
2. Step 2: Convert to fraction form
   3,896.38/5,376.99 = 2,128.15/x
3. Step 3: Cross multiply
   3,896.38x = 5,376.99 × 2,128.15
4. Step 4: Simplify right side
   3,896.38x = 11,443,041.27
5. Step 5: Solve for x
   x = 11,443,041.27/3,896.38
6. Step 6: Final answer
   x = 2,936.84