Finding the Fourth Proportional to 2,908.72, 4,013.40 and 2,123.20

Step by Step Solution

1. Step 1: Write the proportion equation
   2,908.72 : 4,013.40 = 2,123.20 : x
2. Step 2: Convert to fraction form
   2,908.72/4,013.40 = 2,123.20/x
3. Step 3: Cross multiply
   2,908.72x = 4,013.40 × 2,123.20
4. Step 4: Simplify right side
   2,908.72x = 8,521,250.88
5. Step 5: Solve for x
   x = 8,521,250.88/2,908.72
6. Step 6: Final answer
   x = 2,929.55