Finding the Fourth Proportional to 5,215, 7,196.72 and 2,857.16

Step by Step Solution

1. Step 1: Write the proportion equation
   5,215 : 7,196.72 = 2,857.16 : x
2. Step 2: Convert to fraction form
   5,215/7,196.72 = 2,857.16/x
3. Step 3: Cross multiply
   5,215x = 7,196.72 × 2,857.16
4. Step 4: Simplify right side
   5,215x = 20,562,180.52
5. Step 5: Solve for x
   x = 20,562,180.52/5,215
6. Step 6: Final answer
   x = 3,942.89