Ashraf purchased Tk. 3000 worth of traveler's checks. If each check was worth either Tk. 100 or Tk. 250, which of the following cannot be the number to Tk. 100 checks purchased?
A
10
B
5
C
18
D
20
Correct Answer: 18
১০০*১৮=১৮০০৩০০০-১৮০০=১২০০.now if we divide 1200/250. We Won't get a full number