Finding the Fourth Proportional to 3,721.92, 5,136.71 and 2,129.15

Step by Step Solution

1. Step 1: Write the proportion equation
   3,721.92 : 5,136.71 = 2,129.15 : x
2. Step 2: Convert to fraction form
   3,721.92/5,136.71 = 2,129.15/x
3. Step 3: Cross multiply
   3,721.92x = 5,136.71 × 2,129.15
4. Step 4: Simplify right side
   3,721.92x = 10,936,789.77
5. Step 5: Solve for x
   x = 10,936,789.77/3,721.92
6. Step 6: Final answer
   x = 2,938.48