Finding the Fourth Proportional to 8,651.81, 12,978.63 and 3,971.03

Step by Step Solution

1. Step 1: Write the proportion equation
   8,651.81 : 12,978.63 = 3,971.03 : x
2. Step 2: Convert to fraction form
   8,651.81/12,978.63 = 3,971.03/x
3. Step 3: Cross multiply
   8,651.81x = 12,978.63 × 3,971.03
4. Step 4: Simplify right side
   8,651.81x = 51,538,464.20
5. Step 5: Solve for x
   x = 51,538,464.20/8,651.81
6. Step 6: Final answer
   x = 5,956.96