total answers are 6

there is 1 perfect solution, lets say 3 marks(1 mk each) with probability= 1/6

2 answers with no correct annswer (0 mks) with prob=2/6=1/3

3 answers with just 1 correcrt answer( 1 mk) wit hprob= 3/6 =1/2

 

hence required avg

= 3(1/6)+(0)1/3+(1/2)1

=1/2+1/2

=1

hope it was helpful

 

rate if right

nudge if wrong/doubtful