Finding the Fourth Proportional to 11,399.06, 15,718.29 and 7,412.78

Step by Step Solution

1. Step 1: Write the proportion equation
   11,399.06 : 15,718.29 = 7,412.78 : x
2. Step 2: Convert to fraction form
   11,399.06/15,718.29 = 7,412.78/x
3. Step 3: Cross multiply
   11,399.06x = 15,718.29 × 7,412.78
4. Step 4: Simplify right side
   11,399.06x = 116,516,147.15
5. Step 5: Solve for x
   x = 116,516,147.15/11,399.06
6. Step 6: Final answer
   x = 10,221.56