Finding the Fourth Proportional to 2,109.93, 2,911.68 and 1,165.78

Step by Step Solution

1. Step 1: Write the proportion equation
   2,109.93 : 2,911.68 = 1,165.78 : x
2. Step 2: Convert to fraction form
   2,109.93/2,911.68 = 1,165.78/x
3. Step 3: Cross multiply
   2,109.93x = 2,911.68 × 1,165.78
4. Step 4: Simplify right side
   2,109.93x = 3,394,378.31
5. Step 5: Solve for x
   x = 3,394,378.31/2,109.93
6. Step 6: Final answer
   x = 1,608.77