Question

20 passengers are to travelled by a doubled decked bus which can accommodate 13 in the upper deck and 7 in the lower deck. The number of ways that they can be distributed if 5 refuse to sit in the upper deck and 8 refuse to sit in the lower deck is:

(a) 25
(b) 21
(c) 18
(d) 15

Answer 1

b. 21 is the answer