Finding the Fourth Proportional to 3,891.88, 5,803.55 and 3,856.78

Step by Step Solution

1. Step 1: Write the proportion equation
   3,891.88 : 5,803.55 = 3,856.78 : x
2. Step 2: Convert to fraction form
   3,891.88/5,803.55 = 3,856.78/x
3. Step 3: Cross multiply
   3,891.88x = 5,803.55 × 3,856.78
4. Step 4: Simplify right side
   3,891.88x = 22,382,996.29
5. Step 5: Solve for x
   x = 22,382,996.29/3,891.88
6. Step 6: Final answer
   x = 5,751.20