Finding the Fourth Proportional to 2,604.79, 3,908.40 and 1,290.16

Step by Step Solution

1. Step 1: Write the proportion equation
   2,604.79 : 3,908.40 = 1,290.16 : x
2. Step 2: Convert to fraction form
   2,604.79/3,908.40 = 1,290.16/x
3. Step 3: Cross multiply
   2,604.79x = 3,908.40 × 1,290.16
4. Step 4: Simplify right side
   2,604.79x = 5,042,461.34
5. Step 5: Solve for x
   x = 5,042,461.34/2,604.79
6. Step 6: Final answer
   x = 1,935.84