Finding the Fourth Proportional to 2,081.69, 3,121.91 and 765.14

Step by Step Solution

1. Step 1: Write the proportion equation
   2,081.69 : 3,121.91 = 765.14 : x
2. Step 2: Convert to fraction form
   2,081.69/3,121.91 = 765.14/x
3. Step 3: Cross multiply
   2,081.69x = 3,121.91 × 765.14
4. Step 4: Simplify right side
   2,081.69x = 2,388,678.78
5. Step 5: Solve for x
   x = 2,388,678.78/2,081.69
6. Step 6: Final answer
   x = 1,147.47