25 is the answer to your question
Answer:
Step-by-step explanation:
Distance traveled in
hours = 
Distance traveled in 1 hour =
÷ 
÷ 

distance traveled in 3 1/5 hours = 
=
It is necessary to include the term one then you will have the plus three
A)If the order of the speakers is important, we have 20x19x18x17, or 116,280 different options.
b) If order is not important, then we have 20 choose 4, or 4845 different slates. ☺☺☺☺