Question

Bart takes a random sample of 50 students in his seventh grade class and finds that 40% of the sample prefers chocolate ice cream over vanilla ice cream. There are 200 students in the seventh grade. Based on the sample proportion , How many students in the seventh grade would be expected to prefer chocolate ice cream over vanilla ice cream??????

Which answer is correct 40,80,50,200

Answer 1

40% of 50 is 20.  So, 20/50 students who take the random sample prefer chocolate over vanilla ice cream.  In order to find the number of students who prefer chocolate over vanilla ice cream out of 200 students in total, it is best to set up a proportion.  Here:  20/50=x/200.  Once you solve the proportion you will get x as 80.

Hope the explanation helped!