Finding the Fourth Proportional to 5,215.10, 7,196.81 and 2,857.19

Step by Step Solution

1. Step 1: Write the proportion equation
   5,215.10 : 7,196.81 = 2,857.19 : x
2. Step 2: Convert to fraction form
   5,215.10/7,196.81 = 2,857.19/x
3. Step 3: Cross multiply
   5,215.10x = 7,196.81 × 2,857.19
4. Step 4: Simplify right side
   5,215.10x = 20,562,657.27
5. Step 5: Solve for x
   x = 20,562,657.27/5,215.10
6. Step 6: Final answer
   x = 3,942.91