Finding the Fourth Proportional to 2,721.84, 4,078.20 and 2,620.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,721.84 : 4,078.20 = 2,620.72 : x
2. Step 2: Convert to fraction form
   2,721.84/4,078.20 = 2,620.72/x
3. Step 3: Cross multiply
   2,721.84x = 4,078.20 × 2,620.72
4. Step 4: Simplify right side
   2,721.84x = 10,687,820.30
5. Step 5: Solve for x
   x = 10,687,820.30/2,721.84
6. Step 6: Final answer
   x = 3,926.69