Finding the Fourth Proportional to 3,715.89, 5,131.40 and 2,391.90

Step by Step Solution

1. Step 1: Write the proportion equation
   3,715.89 : 5,131.40 = 2,391.90 : x
2. Step 2: Convert to fraction form
   3,715.89/5,131.40 = 2,391.90/x
3. Step 3: Cross multiply
   3,715.89x = 5,131.40 × 2,391.90
4. Step 4: Simplify right side
   3,715.89x = 12,273,777.91
5. Step 5: Solve for x
   x = 12,273,777.91/3,715.89
6. Step 6: Final answer
   x = 3,303.05