Finding the Fourth Proportional to 3,617.89, 4,992.40 and 2,105.21

Step by Step Solution

1. Step 1: Write the proportion equation
   3,617.89 : 4,992.40 = 2,105.21 : x
2. Step 2: Convert to fraction form
   3,617.89/4,992.40 = 2,105.21/x
3. Step 3: Cross multiply
   3,617.89x = 4,992.40 × 2,105.21
4. Step 4: Simplify right side
   3,617.89x = 10,510,050.40
5. Step 5: Solve for x
   x = 10,510,050.40/3,617.89
6. Step 6: Final answer
   x = 2,905.02