Question

A company produces steel rods. The lengths of the steel rods are normally distributed with a mean of 93.4- cm and a standard deviation of 0.6-cm. Find the proportion of steel rods with lengths between 92 cm and 95.1 cm. Enter your answer as a number accurate to 4 decimal places.

Answer 1

Sold A company produces Normally distributed with a mean (4) standbord deviation (6) = 0.6cm steed rods with lengths between -1.4 LZ <_/07 Givent a steel rods, i.e. 93.4 com proportion of 0.6 < Z 9 P 0.6 92cm and 95.1 cm ines P(92 < x < 95.) =p(12-24 xode 95.1–93.4 0.6 > P(-2.33 2 2 < 2.83) p(222-83) -p(72-2-33) standaod normal table T using 0.0099 0.9977 0.9878 PC92 < x <9501) = 0.9878 .ܶ܇

(2) A company produces steel rods, Noonally distributed with mean des 155.6 standard deviation 6=2cm. probability that rod less than 159.2cm P(x< 159.2) = = P(x-le 14:2-1956 *P(2239 pl Z<1-8) standard Normal table using >> 019640696 0.9641 .: P(x2159.2) = 0.9641