30 POINTS AND BRAINLIEST PLEASE HELP!!! 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; 31 have a green ribbon and a white ribbon; 38 have a blue ribbon and a white ribbon. 16 have all three ribbons. How many dogs have not learned any tricks?
It all equals 360º and there are two of each angle. So, we can add 5x+5x+(3x+20)+(3x+20)=360º. Subtracted 40 and simplify. So 16x=320.So divide by 16 and you get that x=20.