Finding the Fourth Proportional to 2,605.76, 3,908.59 and 756.80

Step by Step Solution

1. Step 1: Write the proportion equation
   2,605.76 : 3,908.59 = 756.80 : x
2. Step 2: Convert to fraction form
   2,605.76/3,908.59 = 756.80/x
3. Step 3: Cross multiply
   2,605.76x = 3,908.59 × 756.80
4. Step 4: Simplify right side
   2,605.76x = 2,958,020.91
5. Step 5: Solve for x
   x = 2,958,020.91/2,605.76
6. Step 6: Final answer
   x = 1,135.19