Finding the Fourth Proportional to 3,453.96, 5,180.89 and 856.88

Step by Step Solution

1. Step 1: Write the proportion equation
   3,453.96 : 5,180.89 = 856.88 : x
2. Step 2: Convert to fraction form
   3,453.96/5,180.89 = 856.88/x
3. Step 3: Cross multiply
   3,453.96x = 5,180.89 × 856.88
4. Step 4: Simplify right side
   3,453.96x = 4,439,401.02
5. Step 5: Solve for x
   x = 4,439,401.02/3,453.96
6. Step 6: Final answer
   x = 1,285.31