Finding the Fourth Proportional to 5,139.09, 7,090.85 and 3,123.54

Step by Step Solution

1. Step 1: Write the proportion equation
   5,139.09 : 7,090.85 = 3,123.54 : x
2. Step 2: Convert to fraction form
   5,139.09/7,090.85 = 3,123.54/x
3. Step 3: Cross multiply
   5,139.09x = 7,090.85 × 3,123.54
4. Step 4: Simplify right side
   5,139.09x = 22,148,561.42
5. Step 5: Solve for x
   x = 22,148,561.42/5,139.09
6. Step 6: Final answer
   x = 4,309.82