the ratio is given as follows,
tofu tacos: chicken tacos: fish tacos
1 : 2 : 3
As the food truck sells 12 tofu tacos,
it means 1 ratio is representing 12
so chicken tacos is 2 ratioo = 2 x 12 = 24 chicken tacos
fish tacos is 3 ratio = 3 x 12 = 36 fist tacos.
So total is 12 + 24 + 36 = 72 tacos.
we can do cross-verification also
tofu tacos: chicken tacos: fish tacos
12 : 24 : 36