Finding the Fourth Proportional to 7,123.38, 10,675.78 and 5,155.64

Step by Step Solution

1. Step 1: Write the proportion equation
   7,123.38 : 10,675.78 = 5,155.64 : x
2. Step 2: Convert to fraction form
   7,123.38/10,675.78 = 5,155.64/x
3. Step 3: Cross multiply
   7,123.38x = 10,675.78 × 5,155.64
4. Step 4: Simplify right side
   7,123.38x = 55,040,478.40
5. Step 5: Solve for x
   x = 55,040,478.40/7,123.38
6. Step 6: Final answer
   x = 7,726.74