Answer:
e) 294 children
Step-by-step explanation:
Since there are 394 children in total and 169 do not like either ice-cream, the number of children who likes at least 1 ice cream is
394 - 169 = 225 children
Out of 225 children, 150 like pistachio icecream, some of them may like both. Therefore the number of children who likes ONLY chocolate icecream is
225 - 150 = 75 children
Similarly, out of 225 children, 175 like chocolate icecream, some of them may like both. Therefore the number of children who likes ONLY pitaschio icecream is
225 - 175 = 50 children
So the total number of children who like at most only 1 kind of ice cream is
75 + 50 + 169 = 294 children