Finding the Fourth Proportional to 8,538.57, 11,779.83 and 5,180.15

Step by Step Solution

1. Step 1: Write the proportion equation
   8,538.57 : 11,779.83 = 5,180.15 : x
2. Step 2: Convert to fraction form
   8,538.57/11,779.83 = 5,180.15/x
3. Step 3: Cross multiply
   8,538.57x = 11,779.83 × 5,180.15
4. Step 4: Simplify right side
   8,538.57x = 61,021,315.82
5. Step 5: Solve for x
   x = 61,021,315.82/8,538.57
6. Step 6: Final answer
   x = 7,146.55