Finding the Fourth Proportional to 2,880.72, 3,942.18 and 2,820.24

Step by Step Solution

1. Step 1: Write the proportion equation
   2,880.72 : 3,942.18 = 2,820.24 : x
2. Step 2: Convert to fraction form
   2,880.72/3,942.18 = 2,820.24/x
3. Step 3: Cross multiply
   2,880.72x = 3,942.18 × 2,820.24
4. Step 4: Simplify right side
   2,880.72x = 11,117,893.72
5. Step 5: Solve for x
   x = 11,117,893.72/2,880.72
6. Step 6: Final answer
   x = 3,859.41