Finding the Fourth Proportional to 3,977.78, 5,964.90 and 2,128.54

Step by Step Solution

1. Step 1: Write the proportion equation
   3,977.78 : 5,964.90 = 2,128.54 : x
2. Step 2: Convert to fraction form
   3,977.78/5,964.90 = 2,128.54/x
3. Step 3: Cross multiply
   3,977.78x = 5,964.90 × 2,128.54
4. Step 4: Simplify right side
   3,977.78x = 12,696,528.25
5. Step 5: Solve for x
   x = 12,696,528.25/3,977.78
6. Step 6: Final answer
   x = 3,191.86