Question

Question 14 (1 point) Suppose that the time-to-failure of a system has a distribution with the following pdf: f(x)=0.1e-0.lx What is the probability that the failure occurs between 5 and 20? [hint: similar to Question 1. Homework 7] a). 0.23 b). 0.47 c). 0.088d). O Your answer Question 15 (1 point) The diameter of a metal shaft used in a disk-drive unit is normally distributed with mean 0.25 in. and std. dev. 0.0005 in. The specification on the shaft have been established as (0.25-0.002 in, 0.25+0.002 in) What fraction of the shafts produced conform to specifications? [hint: similar to Question 3, Homework 8] a). O b ). 0. 5 c ). 0.9 d). almost 1 Your answer:

Answer 1

Question 14 f- 0.0 8 -011 oile = ole lo - 0. jx 5 -0-) x 20 ๆ - 4. 6665 - 0.1353 - 0.4 Tophon b

Question 15 X~ c 0.25, 0.0005) specification draft 0.25 -0.002 and 0.25+ 0.0002 PL 0.25-0.002 <x< 0.25 +0.0002] [ 0.25 -0.002 – 0.25, ze 0.25 + 0.25% ze 0.25 +0.0002 -0.254 0.0005 0.0005 =P[4K ZL 4 = 0.9999 from Normal e almost 1 option d table