Finding the Fourth Proportional to 13,018.80, 19,413.88 and 12,900.39

Step by Step Solution

1. Step 1: Write the proportion equation
   13,018.80 : 19,413.88 = 12,900.39 : x
2. Step 2: Convert to fraction form
   13,018.80/19,413.88 = 12,900.39/x
3. Step 3: Cross multiply
   13,018.80x = 19,413.88 × 12,900.39
4. Step 4: Simplify right side
   13,018.80x = 250,446,712.34
5. Step 5: Solve for x
   x = 250,446,712.34/13,018.80
6. Step 6: Final answer
   x = 19,237.31