Finding the Fourth Proportional to 3,986.87, 5,981.37 and 3,551.11

Step by Step Solution

1. Step 1: Write the proportion equation
   3,986.87 : 5,981.37 = 3,551.11 : x
2. Step 2: Convert to fraction form
   3,986.87/5,981.37 = 3,551.11/x
3. Step 3: Cross multiply
   3,986.87x = 5,981.37 × 3,551.11
4. Step 4: Simplify right side
   3,986.87x = 21,240,502.82
5. Step 5: Solve for x
   x = 21,240,502.82/3,986.87
6. Step 6: Final answer
   x = 5,327.61