Dogs in the GoodDog Obedience School win a blue ribbon for learning how to sit, a green ribbon for learning how to roll over, and a white ribbon for learning how to stay. There are 100 dogs in the school.

62 have blue ribbons,55 have green ribbons, and 63 have white ribbons.

32 have a blue ribbon and a green ribbon; 37 have a green ribbon and a white ribbon; 39have a blue ribbon and a white ribbon.

16 have all three ribbons.

How many dogs have not learned any tricks?

Guest Dec 16, 2019

#2**+1 **

Ok, I unfortunately do not have a venn diagram to upload, but I do have one on paper.

1. Draw a venn diagram with 3 circles that are overlapping, and label the circles their own colors.

2. put 16 in the middle, where they all intersect.

3. Fill in each intersection, but subtract 16 everytime. (for example, 32 have blue and green. so 32-16=16. So put 16 in the blue and green intersection)

4. once you're done. add up the whole circle, including the middle and the intersections. (e.x. 23+16+16=55. and then you subtract 55 from 62, since it says that they have 62 blue ribbons, so in total, you have 7 dogs with just blue ribbons)

5. since the question is asking you for how many dogs dont have any ribbons, you can count all of them up, and subtract that by 100.

(it's 12)

Guest Dec 16, 2019