Of the 50 students in an undergraduate statistics class, 60% send email and/or text messages during any given lecture. they have a 50/50 chance of being caught by their professor, who is not amused by such unprofessional conduct. the eagle-eyed professor never charges an innocent student. what is the probability a student sends an email and/or text message during lecture and gets caught?

0.3 or 30%

Step-by-step explanation:

Since no innocent student will ever be caught, the probability that a student sends an email and/or text message during a lecture AND gets caught is given by the product of the probability of a student sending a message (60%) by the probability of the professor catching them (50%) :

The probability is 0.3 or 30%.

a 4/6 = 9/12   not proportional

step-by-step explanation:

to find which are not proportional, we can use cross products

if it is true, they are proportional.   if it is not true, they are not proportional.

a 4/6 = 9/12

4* 12 = 6*9

48 = 54

not this is not proportional  

b 2/3 = 12/18  

2* 18 = 3 * 12

36 = 36

this is proportional

c 5/4 = 10/8  

5*8 = 4*10

40 = 40

this is proportional

d 7/5 = 35/25

7*25 = 5 * 35

175 = 175

is proportional