Finding the Fourth Proportional to 2,105.18, 3,158.17 and 718.75

Step by Step Solution

1. Step 1: Write the proportion equation
   2,105.18 : 3,158.17 = 718.75 : x
2. Step 2: Convert to fraction form
   2,105.18/3,158.17 = 718.75/x
3. Step 3: Cross multiply
   2,105.18x = 3,158.17 × 718.75
4. Step 4: Simplify right side
   2,105.18x = 2,269,934.69
5. Step 5: Solve for x
   x = 2,269,934.69/2,105.18
6. Step 6: Final answer
   x = 1,078.26