Finding the Fourth Proportional to 3,856.56, 5,321.58 and 2,178.18

Step by Step Solution

1. Step 1: Write the proportion equation
   3,856.56 : 5,321.58 = 2,178.18 : x
2. Step 2: Convert to fraction form
   3,856.56/5,321.58 = 2,178.18/x
3. Step 3: Cross multiply
   3,856.56x = 5,321.58 × 2,178.18
4. Step 4: Simplify right side
   3,856.56x = 11,591,359.12
5. Step 5: Solve for x
   x = 11,591,359.12/3,856.56
6. Step 6: Final answer
   x = 3,005.62