Answer: 0.2
Explanation:
Given: According to the Venn diagram,
The probability that a teenager eats hamburger and hot dogs P(H∩D)=0.1
The probability that a teenager eats hamburger P(H)= Teenager eats hamburger only + intersection =0.4+0.1=0.5
Now, the probability that a teenager eats hotdogs, given that he/she eats hamburger is given by :-

Hence, the probability that a teenager eats hotdogs, given that he/she eats hamburger= 0.2