Finding the Fourth Proportional to 9,889.75, 13,647.86 and 5,413.78

Step by Step Solution

1. Step 1: Write the proportion equation
   9,889.75 : 13,647.86 = 5,413.78 : x
2. Step 2: Convert to fraction form
   9,889.75/13,647.86 = 5,413.78/x
3. Step 3: Cross multiply
   9,889.75x = 13,647.86 × 5,413.78
4. Step 4: Simplify right side
   9,889.75x = 73,886,511.51
5. Step 5: Solve for x
   x = 73,886,511.51/9,889.75
6. Step 6: Final answer
   x = 7,471.02