Higher Engineering Mathematics

Assign-15-H8152.tex 23/6/2006 15: 14 Page 552

552 STATISTICS AND PROBABILITY

operating conditions and the remainder give too

low a gain.

Calculate the probability that when drawing two

transistors in turn, at random,with replacement,

of having

(a) two satisfactory,

(b) none with low gain,

(c) one with high gain and one satisfactory,

(d) one with low gain and none satisfactory.

Determine the probabilities in (a), (b) and (c)

above if the transistors are drawn without

replacement. (14)