Finding the Fourth Proportional to 3,910.69, 5,865.43 and 1,278.18

Step by Step Solution

1. Step 1: Write the proportion equation
   3,910.69 : 5,865.43 = 1,278.18 : x
2. Step 2: Convert to fraction form
   3,910.69/5,865.43 = 1,278.18/x
3. Step 3: Cross multiply
   3,910.69x = 5,865.43 × 1,278.18
4. Step 4: Simplify right side
   3,910.69x = 7,497,057.46
5. Step 5: Solve for x
   x = 7,497,057.46/3,910.69
6. Step 6: Final answer
   x = 1,917.07