There are 10 rolls of film in a box and 3 are defective. Two rolls are to be selected without replacement. What is the probability of selecting a defective roll followed by another defective roll?

Step-by-step explanation:

Given : Total rolls of film in the box = 10

Defective rolls =3

Probability of selecting first defective roll =

Now , total rolls left = 9

Total defective rolls left = 2

Probability of selecting second defective roll =

Now , the probability of selecting a defective roll followed by another defective roll =

Hence, the probability of selecting a defective roll followed by another defective roll is .

c) the median for town a 30" is greater than the median for town b 25"

step-by-step explanation:

town a, median = q2 = 30

town b, median - q2 = 25

so the median for town a 30" is greater than the median for town b 25"