Finding the Fourth Proportional to 3,986.74, 5,978.37 and 2,011.15

Step by Step Solution

1. Step 1: Write the proportion equation
   3,986.74 : 5,978.37 = 2,011.15 : x
2. Step 2: Convert to fraction form
   3,986.74/5,978.37 = 2,011.15/x
3. Step 3: Cross multiply
   3,986.74x = 5,978.37 × 2,011.15
4. Step 4: Simplify right side
   3,986.74x = 12,023,398.83
5. Step 5: Solve for x
   x = 12,023,398.83/3,986.74
6. Step 6: Final answer
   x = 3,015.85