Finding the Fourth Proportional to 2,609.61, 3,914.48 and 760.78

Step by Step Solution

1. Step 1: Write the proportion equation
   2,609.61 : 3,914.48 = 760.78 : x
2. Step 2: Convert to fraction form
   2,609.61/3,914.48 = 760.78/x
3. Step 3: Cross multiply
   2,609.61x = 3,914.48 × 760.78
4. Step 4: Simplify right side
   2,609.61x = 2,978,058.09
5. Step 5: Solve for x
   x = 2,978,058.09/2,609.61
6. Step 6: Final answer
   x = 1,141.19