Finding the Fourth Proportional to 3,978.76, 5,961.01 and 2,658.51

Step by Step Solution

1. Step 1: Write the proportion equation
   3,978.76 : 5,961.01 = 2,658.51 : x
2. Step 2: Convert to fraction form
   3,978.76/5,961.01 = 2,658.51/x
3. Step 3: Cross multiply
   3,978.76x = 5,961.01 × 2,658.51
4. Step 4: Simplify right side
   3,978.76x = 15,847,404.70
5. Step 5: Solve for x
   x = 15,847,404.70/3,978.76
6. Step 6: Final answer
   x = 3,983.01