School Survey?

Question: In a survey of 100 students at Hill Middle School, 70 said they like vanilla yogurt, and 60 said they liked peach yogurt, and 50 said they liked both. How many of the students surveyed did not like either flavor?





I don't know how to start this problem.

School Survey?
Well, first draw 2 circles that are kind of overlaping each other like this picture: http://www.atlasbooks.com/marktplc/image...





the first area is "vanilla yogurt", and the other is "peach yogurt" and the one in the middle is the area where the students who liked "both"





First you have to put the number of students who liked both, since they also fall in the category of peach or vanilla. So, 50 like both and 70 students like only vanilla, so 70-50 is 20 and that is the number of students who only like vanilla, this number goes in the "vanilla yogurt" area. Then you do the same with the peach, 60-50 is 10, and that is the number you put in the "peach yogurt" area.





Now you know the numer of each group, so you take those numbers and sum them: 20+10+50=80.


And the excercise says "how many did not like either flavor", so you take 100 and subtract 80= 20!





try to do this on your own with different number, and remeber to first put the number that goes in the overlapping area.... ;) good luck
Reply:ehhh theres a 100 right?


so there are 50 that like both


subtarct 50 from peach and vanilla


u are left with


10 20


add 10 20 and 50 which is 80


subtract that from 100 and u get 20