Finding the Fourth Proportional to 5,128.54, 7,077.30 and 2,890.42

Step by Step Solution

1. Step 1: Write the proportion equation
   5,128.54 : 7,077.30 = 2,890.42 : x
2. Step 2: Convert to fraction form
   5,128.54/7,077.30 = 2,890.42/x
3. Step 3: Cross multiply
   5,128.54x = 7,077.30 × 2,890.42
4. Step 4: Simplify right side
   5,128.54x = 20,456,369.47
5. Step 5: Solve for x
   x = 20,456,369.47/5,128.54
6. Step 6: Final answer
   x = 3,988.73