Question

3. Approximate the probabilties above using the standard deviation rule: 8. A. It was found that the mean length of 100 parts produced by a lathe was 20.05 probablity that a part selected at random would have a length between 20.03 mm and 20.08 mm with a standard deviation of 0,02 mm iu Find the

Answer 1

Z is the random vaudle flowing standard IS Let φ(2) betlu eclf loutdnormal sptibuhon -l- φ(-2) Kl-0.02275-0, 9772ら 097725 0.15966 = 10.91959

ф(2)-ф(-2) p (3). Ф(-3) ~095 45 ~0.9973 2 σ(2)-1 ~ 0.95 45 2(3) 1 0 9973 2 0(2) ~ 1.9545 = 0.97725 2 2 2 ф(2) ~10.97725 Av. 084135t 097725 -1 Awi

Let K be the cmdom vestialle d en atie wc"ל 2005 with a 8|anclard den ahen 얼 0.02 ić, ~ N (20.05, 0.02 2 2 We l cure to .ncl P( 2013 〈χく20.08 P(20.03くく20.08) 20 0 3-0-o9 X- 2o 20.05 0.15)_ d (o.1 0.559 0 53 98 二 0, 0198 Awy ort selected at reudom woulel heuq Ro