<span>y in (-oo:+oo)
(3*y+6)/11 = -9 // + 9
(3*y+6)/11+9 = 0
(3*y+6)/11+(9*11)/11 = 0
3*y+9*11+6 = 0
3*y+105 = 0
(3*y+105)/11 = 0
(3*y+105)/11 = 0 // * 11
3*y+105 = 0
3*y+105 = 0 // - 105
3*y = -105 // : 3
y = -105/3
y = -35
y = -35</span>
the first two professors did not know if everyone wanted coffee because the third professor had to choose yes or no if he wanted coffee. the first two professors were waiting for the third to say something, and when he said no, they knew he did not want coffee. if one of the first two professors said no, the answer would be no.
Lower quartile (xL): 27
Upper quartile (xU): 65
<span>Interquartile range (xU-xL): 38</span>
Your answer is 12 because 8*4=24 and 3*4=12 Your answer is 12