Finding the Fourth Proportional to 3,927.69, 5,420.18 and 2,355.78

Step by Step Solution

1. Step 1: Write the proportion equation
   3,927.69 : 5,420.18 = 2,355.78 : x
2. Step 2: Convert to fraction form
   3,927.69/5,420.18 = 2,355.78/x
3. Step 3: Cross multiply
   3,927.69x = 5,420.18 × 2,355.78
4. Step 4: Simplify right side
   3,927.69x = 12,768,739.86
5. Step 5: Solve for x
   x = 12,768,739.86/3,927.69
6. Step 6: Final answer
   x = 3,250.95