Finding the Fourth Proportional to 10,647.72, 15,978.84 and 5,457.24

Step by Step Solution

1. Step 1: Write the proportion equation
   10,647.72 : 15,978.84 = 5,457.24 : x
2. Step 2: Convert to fraction form
   10,647.72/15,978.84 = 5,457.24/x
3. Step 3: Cross multiply
   10,647.72x = 15,978.84 × 5,457.24
4. Step 4: Simplify right side
   10,647.72x = 87,200,364.80
5. Step 5: Solve for x
   x = 87,200,364.80/10,647.72
6. Step 6: Final answer
   x = 8,189.58