Finding the Fourth Proportional to 3,960.80, 5,466.72 and 2,389.76

Step by Step Solution

1. Step 1: Write the proportion equation
   3,960.80 : 5,466.72 = 2,389.76 : x
2. Step 2: Convert to fraction form
   3,960.80/5,466.72 = 2,389.76/x
3. Step 3: Cross multiply
   3,960.80x = 5,466.72 × 2,389.76
4. Step 4: Simplify right side
   3,960.80x = 13,064,148.79
5. Step 5: Solve for x
   x = 13,064,148.79/3,960.80
6. Step 6: Final answer
   x = 3,298.36