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1- marketing firm is considering making up for three new hires. Given its specif

ID: 1139239 • Letter: 1

Question

1- marketing firm is considering making up for three new hires. Given its specific needs, the management feels that there is a 60% chance of hiring at least two candidates. There is only a 6% chance that it will not make any hires and a 16% chance that it will make all three hires.

a. What is the probability that the firm will make at least one hire? (Round your answer to 2 decimal places.) Probability b. Find the expected value and the standard deviation of the number of hires. (Round your final answers to 2 decimal places.) Expected value Standard deviation

Explanation / Answer

a. The probability of at least 1 hire = 1 - (probability of no new hire)

= 1 - 0.06 = 0.94

2. Expected value of new hires = Summation of (No. of hires*probability of hire)

= 0(0.06) + 1(0.34) + 2(0.44) + 3(0.16) = 1.7

How did we find P(1)? P(1) = 1 - P(0) - P(<=2)

1 - 0.06 - 0.60 = 0.34

P(2) = P(<=2) - P(3) = 0.60 - 0.16 = 0.44

1.7 is the expected value of the no. of hires.

Standard Deviation = (Summation(( x - mean)2 * P(x)))1/2

= (0-1.7)20.06 + (1 - 1.7)2(0.34) + (2-1.7)20.44 + (3-1.7)20.16

= 0.1734 + 0.1666 + 0.0396 + 0.2704 = (0.65)1/2 = 0.806

Thus, 0.806 is the standard deviation