3/8 said yes and 5/8 said no...

it means that 5/8 - 3/8 = 2/8 more pupils said no than yes...

it is said in the question that 46 more pupils said no than yes

=> 2/8 = 46

the total number of pupils is given by 1 or 8/8

if,

2/8 -> 46

8/8 -> 46 / (2/8) * (8/8)

=184

Answer: 184 pupils