Question

• Walmart is seeking to hire new employees at its location in Oxnard. Applicants were told to show up for a face to face interview and were given numbers ranging from 3-49. Assume that all the applicants showed up for the interview:

(a) Find the probability of selecting a prime number

(b) Find the probability of selecting either a prime number or an odd number

© Find the probability of selecting a square number or an even number. A square number is a number that is derived when a number is multiplied by itself. For example, 100 is a square number (because 10x10=100)

(d) Find the probability of selecting a number that is even given that it is divisible by 3

e) Find the probability of selecting an odd number given that it is a square number.

Answer 1

All applicants showed up, so the total number of outcomes( i.e., number of elements in the sample space )  is given by: n(S) = (49-3)+1 = 47

(a)

Let E1 be an event of selecting a prime number ranging 3-49.

So, E1 = {3,5,7,11,13,17,19,23,29,31,37,41,43,47}

i.e., n(E1) = 14

Therefore, P( E1 ) = n(E1) / n(S) = 14 / 47 =0.2978

(b)

Let E2 be an event of selecting either a prime number or an odd number ranging 3-49.

So, E2 = {3,5,7,9,11,13,15,17,19,21,23,25,27,29,31,33,35,37,39,41,43,45,47,49)

i.e., n( E2 ) = 24

Therefore, P(E2) = n(E2) / n(S) = 24 / 47 = 0.51

(c)

Let E3 be an event of selecting a square number or an even number ranging 3-49.

So, E3 = {4,6,8,10,12,14,16,18,20,22,24,26,28,30,32,34,36,38,40,42,44,46,48,9,25,49}

i.e., n( E3 ) = 26

Therefore, P(E3) = n(E3) / n(S) = 26 / 47 =0.5532.

(d)

Let E4 be an event of selecting an even number that is divisible by 3 ranging 3-49.

So, E3 = {6,12,18,24,30,36,42,48}

i.e., n( E4 ) = 8

Therefore, P(E4) = n(E4) / n(S) = 8 / 47 = 0.17