12. I assume 
denotes the complement of A, so
Then by definition of conditional probability,
13. By inclusion/exclusion,
-16t² + 32t + 128 = 0
-16t² + 64t - 32t + 128 = 0
-16t(t - 4) - 32(t - 4)
(-16t - 32)(t - 4) = 0
-16t -32 = 0 t - 4 = 0
-16t = 32 t = 4
t = -2
t = -2 and t = 4 are the values that makes S = 0.
Yes, because if you apply either of these values alone, S will be 0.
The range for boys is 60 as for girls the range is 80. The median for boys is 90 and for girl 110.
Raymond would only pay 154 for the video game system. This is because you subtract 12% from 175.
