Finding the Fourth Proportional to 2,608.61, 3,912.98 and 759.78

Step by Step Solution

1. Step 1: Write the proportion equation
   2,608.61 : 3,912.98 = 759.78 : x
2. Step 2: Convert to fraction form
   2,608.61/3,912.98 = 759.78/x
3. Step 3: Cross multiply
   2,608.61x = 3,912.98 × 759.78
4. Step 4: Simplify right side
   2,608.61x = 2,973,000.15
5. Step 5: Solve for x
   x = 2,973,000.15/2,608.61
6. Step 6: Final answer
   x = 1,139.69