Finding the Fourth Proportional to 10,885.68, 16,328.16 and 3,960

Step by Step Solution

1. Step 1: Write the proportion equation
   10,885.68 : 16,328.16 = 3,960 : x
2. Step 2: Convert to fraction form
   10,885.68/16,328.16 = 3,960/x
3. Step 3: Cross multiply
   10,885.68x = 16,328.16 × 3,960
4. Step 4: Simplify right side
   10,885.68x = 64,659,513.60
5. Step 5: Solve for x
   x = 64,659,513.60/10,885.68
6. Step 6: Final answer
   x = 5,939.87