A survey of 535 adults aged 18-24 year olds was conducted in which they were asked what they did last Friday night.

Question

A survey of 535 adults aged 18-24 year olds was conducted in which they were asked what they did last Friday night. It found:

1. 167 hung out with friends
2. 180 ate pizza
3. 27 watched TV and ate pizza, but did not hang out with friends
4. 42 watched TV and hung out with friends, but did not eat pizza
5. 28 hung out with friends and ate pizza, but did not watch TV
6. 38 watched TV, hung out with friends, and ate pizza
7. 62 did not do any of these three activities

How many 18-24-year-olds (of these three activities) only watched TV last Friday night?

Answer 1

Use a Venn diagram

draw a rectangle

inside draw 3 overlapping circles, one for Friends, one for Pizza one for TV

calculate how many just watched TV but didn't hang with Friends or eat Pizza

or try to, as

the numbers don't add up,

they're impossible

as 27 <38, and 28<38, that's impossible