NEED HELP WITH #11

Exhibit 6-1

The assembly time for a product is uniformly distributed between 6 and 10 minutes.

9.Refer to Exhibit 6-1. The mean and the variance of the assembly time are:

a.	4 minutes and 16 (minute)2
b.	8 minutes and 1.1547 minutes
c.	8 minutes and 1.3333 (minute)2
d.	1.1547 minutes and 8 minutes

ANS:C

10.Refer to Exhibit 6-1. The probability of assembling the product between 9 and 11 minutes is

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a.	0.50
b.	0.25
c.	0.20
d.	0.75

ANS:B

11.Refer to Exhibit 6-1. The probability of assembling the product in 7 minutes or more is

a.	0.25
b.	0.75
c.	0.50
d.	0.20

ANS:B