There are 50 pupils in a class o ne_tenth speak French only and 4/5 of the rest speak both languages find the number of students who speak both English and French; number of pupil who speak only English

50 pupils total. 1/10 speak French only. 1/10 of 50 = 5 pupils

4/5 of the rest (the rest = 50-5=45)speak both . 4/5 of 45 = 36 pupils

50 -5 - 36 = 9 remaining pupils

Fr only = 5
Eng and Fr = 36
Eng only =9

Behavioral science is the study of human behaviors and how they can be influenced.  by examining patterns in behavior as well as reactions, individuals with behavioral problems can be more adequately treated, resulting in greater mental health of our society/the public.