Finding the Fourth Proportional to 2,628.72, 3,939.84 and 2,142.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,628.72 : 3,939.84 = 2,142.72 : x
2. Step 2: Convert to fraction form
   2,628.72/3,939.84 = 2,142.72/x
3. Step 3: Cross multiply
   2,628.72x = 3,939.84 × 2,142.72
4. Step 4: Simplify right side
   2,628.72x = 8,441,973.96
5. Step 5: Solve for x
   x = 8,441,973.96/2,628.72
6. Step 6: Final answer
   x = 3,211.44