If 1/3 of the students wanted more fruits and veggies, then that means that 2/3 did not. And of that 2/3, 1/8 of them wanted more seafood.

This means that 1/12 of all the students surveyed wanted more seafood and 1/3 wanted more fruits and veggies. The least common multiple of 3 and 12 (or the LCD of the two fractions) would be
12.Multiplying by 12, we figure out that 4 of them would have wanted more fruits and veggies and only 1 lonely kid wanted more seafood.
Final answer :
12