Henry recorded the number of students present everyday for a total of $40$ days. Also there are a total of $29$ students. Here is the frequency table:
Also it is given that,on exactly half of the days, No more than one student was absent. Find the values of $x,y$.
My try: Obviously $1+2+x+10+y+12=40 \Rightarrow x+y=15$. But I am unable to frame other equation. I found cumulative frequencies as: $1,3,x+3,x+13,28,40.$ But not sure how to proceed?
"On exactly half of the days, no more than one student was absent", i.e. on exactly $20$ days there were $28$ or $29$ students. This gives $y+12=20$, $y=8$ and $x=7$.