Finding the Fourth Proportional to 3,980.52, 5,968.42 and 2,665.78

Step by Step Solution

1. Step 1: Write the proportion equation
   3,980.52 : 5,968.42 = 2,665.78 : x
2. Step 2: Convert to fraction form
   3,980.52/5,968.42 = 2,665.78/x
3. Step 3: Cross multiply
   3,980.52x = 5,968.42 × 2,665.78
4. Step 4: Simplify right side
   3,980.52x = 15,910,494.67
5. Step 5: Solve for x
   x = 15,910,494.67/3,980.52
6. Step 6: Final answer
   x = 3,997.09