Finding the Fourth Proportional to 8,111.28, 11,193.62 and 5,128.46

Step by Step Solution

1. Step 1: Write the proportion equation
   8,111.28 : 11,193.62 = 5,128.46 : x
2. Step 2: Convert to fraction form
   8,111.28/11,193.62 = 5,128.46/x
3. Step 3: Cross multiply
   8,111.28x = 11,193.62 × 5,128.46
4. Step 4: Simplify right side
   8,111.28x = 57,406,032.43
5. Step 5: Solve for x
   x = 57,406,032.43/8,111.28
6. Step 6: Final answer
   x = 7,077.31