SAT Math Question of the Day

Math Category: Algebraic Sets:

Q: In a group of 7 high school friends, 5 like to drink Coke, 2 like to drink Diet Coke, and 1 likes both Coke and Diet Coke. How many do not like either Coke or Diet Coke?

  1. 0
  2. 1
  3. 2
  4. 3
  5. 4

UNANSWERED.

The correct answer is B.

A: 1 is the right answer.

Let's make a chart to figure out this set problem. There are 7 friends, so make the chart 7 columns wide:

1 2  3 4  5 6  7 
          
          

Next fill in the 5 friends who like to drink Coke:
1 2  3 4  5 6  7 
CC CC C   
          

Next fill in the 2 friends who like Diet Coke. Remember that 1 of those friends also likes Coke, so let's say it's friend #5:
1 2  3 4  5 6  7 
CC CC C   
      DCDC  

Now we have filled out the chart with all the information we know. Looking at the chart we see that friend #7 doesn't like either Coke or Diet Coke, so the answer is 1.