Problema Solution
The National Association for Women in Science asked recent high school grads if they had taken certain science classes. Of those surveyed, 28 said they had taken physics, 47 said they had taken chemistry and 13 said they had taken both. Twelve said they had taken neither. How many recent high school grads were surveyed? Show your work.
Answer provided by our tutors
There are two possible answers.
There are 100 responses total (28 + 47 + 13 + 12). So the answer is 100 IF we assume that "28 said they had taken physics" means they have ONLY taken physics.
But otherwise, if we assume that the 13 who took both are also included in the chemistry numbers, then we've counted them twice. So in that case, the answer would be:
28 taking physics
47 taking chemistry
12 who took neither
and we have to subtract 13, for the students we counted twice, once in each class.
28 + 47 + 12 - 13 = 74