Finding the Fourth Proportional to 6,111.48, 8,431.90 and 3,721.28

Step by Step Solution

1. Step 1: Write the proportion equation
   6,111.48 : 8,431.90 = 3,721.28 : x
2. Step 2: Convert to fraction form
   6,111.48/8,431.90 = 3,721.28/x
3. Step 3: Cross multiply
   6,111.48x = 8,431.90 × 3,721.28
4. Step 4: Simplify right side
   6,111.48x = 31,377,409.37
5. Step 5: Solve for x
   x = 31,377,409.37/6,111.48
6. Step 6: Final answer
   x = 5,134.17