Finding the Fourth Proportional to 10,650.16, 15,978.08 and 8,779.47

Step by Step Solution

1. Step 1: Write the proportion equation
   10,650.16 : 15,978.08 = 8,779.47 : x
2. Step 2: Convert to fraction form
   10,650.16/15,978.08 = 8,779.47/x
3. Step 3: Cross multiply
   10,650.16x = 15,978.08 × 8,779.47
4. Step 4: Simplify right side
   10,650.16x = 140,279,074.02
5. Step 5: Solve for x
   x = 140,279,074.02/10,650.16
6. Step 6: Final answer
   x = 13,171.55