<h2>the answer i thinkk is 2/20 because since there ae 20 children, then the brother and sister each have a 1% chance, hope this helped!</h2>
15) factor out cos: cos(x)(sin(x)+1)=0
Now this is true when either cos(x)=0 (x=pi/2 and 3pi/2)
Or when sin(x)=-1 (x=3pi/2)
So it's solutions are pi/2 and 3pi/2
31 hours.
first I times $30 by 15, an I got 450, then I got 1132 and took away 450 and I got 682, finally I divide 682 by 22 and got 31
