Finding the Fourth Proportional to 2,896.28, 3,978.17 and 2,840.94

Step by Step Solution

1. Step 1: Write the proportion equation
   2,896.28 : 3,978.17 = 2,840.94 : x
2. Step 2: Convert to fraction form
   2,896.28/3,978.17 = 2,840.94/x
3. Step 3: Cross multiply
   2,896.28x = 3,978.17 × 2,840.94
4. Step 4: Simplify right side
   2,896.28x = 11,301,742.28
5. Step 5: Solve for x
   x = 11,301,742.28/2,896.28
6. Step 6: Final answer
   x = 3,902.16