Finding the Fourth Proportional to 11,426.16, 17,140.80 and 5,578.72

Step by Step Solution

1. Step 1: Write the proportion equation
   11,426.16 : 17,140.80 = 5,578.72 : x
2. Step 2: Convert to fraction form
   11,426.16/17,140.80 = 5,578.72/x
3. Step 3: Cross multiply
   11,426.16x = 17,140.80 × 5,578.72
4. Step 4: Simplify right side
   11,426.16x = 95,623,723.78
5. Step 5: Solve for x
   x = 95,623,723.78/11,426.16
6. Step 6: Final answer
   x = 8,368.84