Finding the Fourth Proportional to 3,131.36, 4,290.28 and 3,090.32

Step by Step Solution

1. Step 1: Write the proportion equation
   3,131.36 : 4,290.28 = 3,090.32 : x
2. Step 2: Convert to fraction form
   3,131.36/4,290.28 = 3,090.32/x
3. Step 3: Cross multiply
   3,131.36x = 4,290.28 × 3,090.32
4. Step 4: Simplify right side
   3,131.36x = 13,258,338.09
5. Step 5: Solve for x
   x = 13,258,338.09/3,131.36
6. Step 6: Final answer
   x = 4,234.05