Finding the Fourth Proportional to 3,980.28, 5,965.52 and 1,638.83

Step by Step Solution

1. Step 1: Write the proportion equation
   3,980.28 : 5,965.52 = 1,638.83 : x
2. Step 2: Convert to fraction form
   3,980.28/5,965.52 = 1,638.83/x
3. Step 3: Cross multiply
   3,980.28x = 5,965.52 × 1,638.83
4. Step 4: Simplify right side
   3,980.28x = 9,776,446.31
5. Step 5: Solve for x
   x = 9,776,446.31/3,980.28
6. Step 6: Final answer
   x = 2,456.22