Finding the Fourth Proportional to 5,409.56, 8,128.02 and 5,190.86

Step by Step Solution

1. Step 1: Write the proportion equation
   5,409.56 : 8,128.02 = 5,190.86 : x
2. Step 2: Convert to fraction form
   5,409.56/8,128.02 = 5,190.86/x
3. Step 3: Cross multiply
   5,409.56x = 8,128.02 × 5,190.86
4. Step 4: Simplify right side
   5,409.56x = 42,191,413.90
5. Step 5: Solve for x
   x = 42,191,413.90/5,409.56
6. Step 6: Final answer
   x = 7,799.42