Finding the Fourth Proportional to 3,965.80, 5,458.98 and 3,965.80

Step by Step Solution

1. Step 1: Write the proportion equation
   3,965.80 : 5,458.98 = 3,965.80 : x
2. Step 2: Convert to fraction form
   3,965.80/5,458.98 = 3,965.80/x
3. Step 3: Cross multiply
   3,965.80x = 5,458.98 × 3,965.80
4. Step 4: Simplify right side
   3,965.80x = 21,649,222.88
5. Step 5: Solve for x
   x = 21,649,222.88/3,965.80
6. Step 6: Final answer
   x = 5,458.98