Finding the Fourth Proportional to 8,690.79, 13,028.39 and 3,142.83

Step by Step Solution

1. Step 1: Write the proportion equation
   8,690.79 : 13,028.39 = 3,142.83 : x
2. Step 2: Convert to fraction form
   8,690.79/13,028.39 = 3,142.83/x
3. Step 3: Cross multiply
   8,690.79x = 13,028.39 × 3,142.83
4. Step 4: Simplify right side
   8,690.79x = 40,945,999.23
5. Step 5: Solve for x
   x = 40,945,999.23/8,690.79
6. Step 6: Final answer
   x = 4,711.42