Question 1197381


{{{E(X) = np = 50(0 .5) = 25}}} correct answers. 

{{{SD(X) =sqrt( npq) =sqrt( 50* 0.5 *0.5)= 3.54 }}}  correct answers. 

Answers may vary. 

In order be convincing, the student would have to answer at least {{{36}}} out of {{{50}}}questions correctly, since {{{36}}} is approximately three standard deviations above the mean. 

Answering fewer than {{{36}}} questions correctly could happen too often, simply {{{due}}}{{{ to}}}{{{ chance}}}.